DOCSLIB.ORG

Statistical Prediction of Waterspout Probability for The

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Statistical Prediction of Waterspout Probability for The 1 STATISTICAL PREDICTION OF WATERSPOUT PROBABILITY FOR THE 2 FLORIDA KEYS 3 1* 2 4 Andrew Devanas , Lydia Stefanova 5 1 6 NOAA/National Weather Service, Key West, FL 2 7 COAPS/Florida State University, Tallahassee, FL 8 9 10 11 Submitted to Weather and Forecasting 12 7 July 2017 13 Revised 24 November 2017, 13 January 2018 14 1* Corresponding author: [email protected] 15 ABSTRACT 16 17 A statistical model of waterspout probability was developed for the wet season (June-September) 18 days over the Florida Keys. An analysis was performed on over 200 separate variables derived 19 from Key West 1200 UTC daily wet season soundings during the period 2006-2014. These 20 variables were separated into two subsets: days on which a waterspout was reported anywhere in 21 the Florida Keys coastal waters, and days on which no waterspouts were reported. Days on 22 which waterspouts were reported were determined from the National Weather Service (NWS) 23 Key West Local Storm Reports. The sounding at Key West was used for this analysis since it 24 was assumed representative of the atmospheric environment over the area evaluated in this study. 25 The probability of a waterspout report day was modeled using multiple logistic regression with 26 selected predictors obtained from the sounding variables. The final model containing eight 27 separate variables was validated using repeated 5-fold cross-validation, and its performance was 28 compared to that of an existing waterspout index used as a benchmark. The performance of the 29 model was further validated in forecast mode using an independent verification wet season data 30 set from 2015-2016 that was not used to define or train the model. The eight-predictor model 31 was found to produce a probability forecast with robust skill relative to climatology and superior 32 to the benchmark waterspout index in both the cross-validation and in the independent 33 verification. 34 2 35 1. Introduction 36 37 The frequency of non-supercell waterspouts in the Florida Keys is higher than any other location 38 in the United States and may be one of the highest in the world, with hundreds of waterspouts 39 occurring each year in the waters surrounding the Florida Keys (Golden 2003). Waterspouts are 40 a marine hazard, and do occasionally come on shore resulting in damage to coastal structures. 41 Objective waterspout guidance for the Key West area is limited, and forecasters rely mainly on 42 subjective techniques and empirical rules of thumb to forecast the possibility of waterspout 43 development. A reliable objective guidance that can be used in combination with available 44 subjective tools would likely aid the forecast process. 45 46 Only a fraction of waterspouts are observed and recorded. During the Lower Keys Waterspout 47 Project in 1969, at least 400 waterspouts were documented (Golden 1974). Golden (1977) 48 estimated that between 50-500 waterspouts occur each year over the Florida Keys coastal waters. 49 Given that approximately 25 waterspouts, on average, are reported during the wet season 50 (estimated from 2006-2014 reports discussed in section 2), waterspouts may be underreported by 51 up to an order of magnitude, a conjecture also made by Golden and Bluestein (1994). Florida 52 Keys waterspouts have been reported in every month of the year, although less frequently from 53 October to May. Waterspout formation is noticeably more frequent during the wet season, June 54 to September, with a primary maximum in June (Fig. 1), consistent with Golden (2003). The 55 months of May and October are considered transition months (dry to wet and wet to dry season 56 respectively), during which midlatitude influences can vary greatly from year to year. Therefore, 57 the transition months were excluded from this study. During the wet season months in the 3 58 present study waterspouts were reported on approximately 19% of all days. 59 60 Rossow (1970) noted that it is not possible to distinguish a likely waterspout day from one that is 61 not, because the weather is nearly the same during the wet season. The atmospheric environment 62 over the Florida Keys exhibits mainly incremental day-to-day variations in the temperature and 63 moisture profile. Because of this, it is difficult to readily differentiate between days that are more 64 favorable for waterspout development and days that are less favorable simply by examining 65 soundings, sounding climatologies, or individual parameters or stability indices derived from the 66 soundings. Nonetheless, the atmosphere over the Florida Keys does experience a degree of 67 variability. For example, tropical features such as easterly waves and tropospheric upper level 68 trough cells traverse the area surrounding the Keys throughout the wet season. Changes in the 69 position and strength of the Bermuda High, as well as the flow off the mainland and Cuba, may 70 result in changes of wind patterns and temperature and moisture profiles. 71 72 Schwiesow (1981), as well as Sioutas and Keul (2007), noted that traditional stability indices in 73 isolation did not perform well as indicators of a favorable waterspout development environment. 74 Several previous efforts to quantify favorable conditions for waterspout development have been 75 done using sounding parameters as well as synoptic scale analysis. Golden and Bluestein (1994) 76 noted that the thermodynamic soundings originating from the NWS Weather Forecast Office in -1 77 Key West, Florida on waterspout days revealed relatively light low-level winds (5-8 m s ), light 78 shear, and abundant moisture in the boundary layer with drier air above. Golden (2003) 79 expressed concern that a mean sounding climatology, or the NWS Key West sounding, could not 80 adequately capture the superadiabatic lapse rates observed in the sub-cloud layer of waterspout- 4 81 producing cumulus observed in his studies. 82 83 Spratt and Choy (1994) examined data from the period 1979-1992 identifying days with at least 84 one waterspout report in conjunction with soundings from Tampa, West Palm Beach, and Cape 85 Canaveral. They determined that light winds at discrete levels through the lower troposphere (up 86 to 500 mb) and total precipitable water vapor levels in excess of 4.1 cm (1.6 in) produced 87 favorable conditions for waterspout development. They combined these sounding-derived 88 parameters with WSR-88D radar information to build a five-step waterspout forecast strategy. 89 90 Brown and Rothfuss (1998) developed a basic waterspout index for the Florida Keys and South 91 Florida which included mean wind direction and speed below 600 mb, as well as a qualifier for 92 whether a waterspout occurred on the previous day. The values obtained were assigned a value 93 of 0.5 or 1 according to a table, and a sum equaling 2 or greater was considered favorable for 94 waterspout development. 95 96 An index developed by Kuiper and van der Haven (2007) used the product of four weighted 97 parameters (0-3 km wind shear, 0-500 m lapse rate, 0-1 km average humidity, and 10 m wind 98 speed) to indicate the risk of waterspout development over the shallow waters of the North Sea 99 off the coast of the Netherlands (the Kuiper Haven Spout Index, or KHS-index). The KHS-index 100 has been implemented in the locally run High Resolution Limited Area Model (HiRLAM) at the 101 Royal Netherlands Meteorological Institute. 102 103 A study of waterspouts over the Adriatic, Ionian, and Aegean Seas by Sioutas and Keul (2007) 5 104 examined several thermodynamic indices derived from proximity sounding data in relation to 105 waterspout development. They found that “fair weather” waterspouts were mainly a result of a 106 preexisting unstable air mass and low wind shear. Of the thermodynamic indices examined in the 107 study, they stated that the K-Index and the Total Totals Index were good indicators of an 108 unstable environment and useful in identifying favorable tornadic and fair weather waterspout 109 environments. Other thermodynamic indices they examined did not perform as well from a 110 predictive standpoint. 111 112 A follow up study (Keul et. al. 2009) examined the performance of the Szilagyi waterspout 113 forecasting technique (Szilagyi 2009) as a predictor for Mediterranean waterspout occurrence. 114 The Szilagyi technique uses a nomogram to compare the difference between sea surface 115 temperature and the 850 mb temperature against the convective cloud depth, and is also available 116 as an index (Szilagyi Waterspout Index). Values of the Szilagyi Waterspout Index range from - 117 10 to 10, with values greater than zero considered a favorable waterspout environment. 118 119 The NASA Applied Meteorology Unit (AMU) at the Kennedy Space Center in Florida used a 120 combination of four factors (monthly climatology, vertical wind profile, precipitable water, and 121 persistence) to determine the weak waterspout (“fair weather” waterspout) potential for the day 122 (Wheeler 2009). The value produced by the methodology is compared to a table to ascertain 123 whether the threat level for the day is low, medium, or high. An AMU follow up study (Watson 124 2011) used a logistic regression technique similar to that in the present study to evaluate the 125 probability of severe weather occurrence at the Kennedy Space Center. However, it did not 126 include a re-evaluation of the weak waterspout methodology outlined in Wheeler (2009). Watson 6 127 (2011) found that using logistic regression did not show an improvement over their existing 128 severe weather likelihood methodology. 129 130 A common thread found through many studies (Spratt and Choy 1994, Brown and Rothfuss 131 1998, Golden 2003, Kuiper and van der Haven 2007, Sioutas and Keul 2007, Wheeler 2009) is 132 the presence of weak lower tropospheric winds and/or weak lower tropospheric shear as a 133 favorable environment for waterspout development.
Load more

Recommended publications
  • Fire Weather Area Forecast Matrices User’S Guide to Decoding the AFW
    Fire Weather Area Forecast Matrices User’s Guide to Decoding the AFW What are the Area Forecast Matrices? The Area Forecast Matrices (AFW) is a table that displays the forecasted weather parameters in 3, 6 and 12 hour intervals out to 7 days in the future. Below is a sample AFW, along with a description of each parameter’s code (blue colored numbers). (1) NCZ510-082100- EASTERN POLK- INCLUDING THE CITIES OF...COLUMBUS 939 AM EST THU DEC 8 2011 (2) DATE THU 12/08/11 FRI 12/09/11 SAT 12/10/11 UTC 3HRLY 09 12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 EST 3HRLY 04 07 10 13 16 19 22 01 04 07 10 13 16 19 22 01 04 07 10 13 16 19 (3) MAX/MIN 51 30 54 32 52 (4) TEMP 39 49 51 41 36 33 32 31 42 51 52 44 39 36 33 32 41 49 50 41 (5) DEWPT 24 21 20 23 26 28 28 26 26 25 25 28 28 26 26 26 26 26 25 25 (6) MIN/MAX RH 29 93 34 78 37 (7) RH 55 32 29 47 67 82 86 79 52 36 35 52 65 68 73 78 53 40 37 51 (8) WIND DIR NW S S SE NE NW NW N NW S S W NW NW NW NW N N N N (9) WIND DIR DEG 33 16 18 12 02 33 31 33 32 19 20 25 33 32 32 32 34 35 35 35 (10) WIND SPD 5 4 5 2 3 0 0 1 2 4 3 2 3 5 5 6 8 8 6 5 (11) CLOUDS CL CL CL FW FW SC SC SC SC SC SC SC SC SC SC SC FW FW FW FW (12) CLOUDS(%) 0 2 1 10 25 34 35 35 33 31 34 37 40 43 37 33 24 15 12 9 (13) VSBY 10 10 10 10 10 10 10 10 (14) POP 12HR 0 0 5 10 10 (15) QPF 12HR 0 0 0 0 0 (16) LAL 1 1 1 1 1 1 1 1 1 (17) HAINES 5 4 4 5 5 5 4 4 5 (18) DSI 1 2 2 (19) MIX HGT 2900 1500 300 3000 2900 400 600 4200 4100 (20) T WIND DIR S NE N SW SW NW NW NW N (21) T WIND SPD 5 3 2 6 9 3 8 13 14 (22) ADI 27 2 5 44 51 5 17
    [Show full text]
  • Supplementary Material Ensemble Lightning Prediction Models for The
    International Journal of Wildland Fire 25(4), 421–432 doi: 10.1071/WF15111_AC © IAWF 2016 Supplementary material Ensemble lightning prediction models for the province of Alberta, Canada Karen D. BlouinA,B,D, Mike D. FlanniganA,B, Xianli WangA,B and Bohdan KochtubajdaC ADepartment of Renewable Resources, University of Alberta, 751 General Services Building, Edmonton, AB T6G 2H1, Canada. BWestern Partnership for Wildland Fire Science, 751 General Services Building, Edmonton, AB T6G 2H1, Canada. CPresent address: Great Lakes Forestry Centre, Canadian Forest Service, Natural Resources Canada, 1219 Queen Street East, Sault Ste. Marie, ON P6A 2E5, Canada. DEnvironment and Climate Change Canada, Meteorological Service of Canada, 9250-49th Street NW, Edmonton, AB T6B 1K5, Canada. ECorresponding author: Email: [email protected] Page 1 of 9 Table S1. Description of upperair parameters and indices For the following equations, unless otherwise stated: Temperature (T) and dewpoint temperature (Td) are in degrees Celsius; numbered subscripts refer to the atmospheric level (mb), and g is acceleration due to gravity Convective An indicator of atmospheric instability, CAPE is a numerical measure of the amount of energy (J/kg) available to a parcel of air if lifted through the Available Potential atmosphere. The positive buoyancy of the parcel can be found by calculating the area on a thermodynamic diagram (Skew-T log-P) between the level of free Energy (CAPE) convection, zLFC, and the equilibrium level, zEQ, where the environment temperature profile is cooler than the parcel temperature. CAPE < 1,000 J/kg indicates a lower likelihood of severe storms while values in excess of 2,000 J/kg and 3,000 J/kg indicate sufficient energy for thunderstorm and severe thunderstorms respectively.
    [Show full text]
  • Lightning-Caused Fires
    786 JOURNAL OF APPLIED METEOROLOGY VOLUME 41 The 2000 Fire Season: Lightning-Caused Fires MIRIAM L. RORIG AND SUE A. FERGUSON Paci®c Northwest Research Station, USDA Forest Service, Seattle, Washington (Manuscript received 22 May 2001, in ®nal form 9 February 2002) ABSTRACT A large number of lightning-caused ®res burned across the western United States during the summer of 2000. In a previous study, the authors determined that a simple index of low-level moisture (85-kPa dewpoint depression) and instability (85±50-kPa temperature difference) from the Spokane, Washington, upper-air soundings was very useful for indicating the likelihood of ``dry'' lightning (occurring without signi®cant concurrent rainfall) in the Paci®c Northwest. This same method was applied to the summer-2000 ®re season in the Paci®c Northwest and northern Rockies. The mean 85-kPa dewpoint depression at Spokane from 1 May through 20 September was 17.78C on days when lightning-caused ®res occurred and was 12.38C on days with no lightning-caused ®res. Likewise, the mean temperature difference between 85 and 50 kPa was 31.38C on lightning-®re days, as compared with 28.98C on non-lightning-®re days. The number of lightning-caused ®res corresponded more closely to high instability and high dewpoint depression than to the total number of lightning strikes in the region. 1. Introduction storms. The Haines index contains a moisture factor in combination with a stability factor to produce a single The summer of 2000 was notable for the number of categorical index used to quantify the risk of wild®re large wild®res that burned across the western United growth.
    [Show full text]
  • The Continuous Haines Index
    A POTENTIAL BREAKTHROUGH IN WILDFIRE MANAGEMENT THE CONTINUOUS HAINES INDEX - A TOOL FOR FORECASTING CATASTROPHIC FIRE ESCALATION Rick McRae, ACT Emergency Services Agency. Forecasting atmospheric stability has long been seen as important. The ACT has used the Pasquill’s Index for decades, and Pasquill’s also gives guidance on the amount of wind swing. After Rick Ochoa spoke on the Haines Index at the 1997 Fire Weather Workshop, the ACT and other jurisdictions have used it. John Bally studies HI extensively in Tasmania and found that it predicted days of elevated fire danger as well as did McArthur Forest Fire Danger index. During operatio9nal evaluation on the mainland many found that it “maxed-out” to often to be of value. HI is capped at a vlaue of 6, and most hot dry days in summer were scoring 6, irrespective of the FDR that day. The onset of frequent violent pyro-convection since 2002 has shown the need for a better index. After the catastrophic 2003 ACT fires, researchers found that there was a growing list of major fire events in which atmospheric stability played an important role. The ability for a vigorous plume to induce mixing down of drier air aloft is a common element. Forecasting of that can be through examination of water vapour satellite imagery or by deriving stability indices from Aerological Diagrams. By analysing the atmosphere above a large set of fire events, Mills and McCaw derived C-Haines. This new tool wasv developed by the Centre for Australian Weather and Climate Research (BoM & CSIRO) as part of the BushfireCooperative Rresearch Centre.
    [Show full text]
  • SW Fire Weather Annual Operating Plan
    SOUTHWEST AREA FIRE WEATHER ANNUAL OPERATING PLAN 2018 Arizona New Mexico West Texas Oklahoma Panhandle 2018 SOUTHWEST AREA FIRE WEATHER ANNUAL OPERATING PLAN SECTION PAGE I. INTRODUCTION 1 II. SIGNIFICANT CHANGES SINCE PREVIOUS PLAN 1 III. SERVICE AREAS AND ORGANIZATIONAL DIRECTORIES 2 IV. NATIONAL WEATHER SERVICE SERVICES AND RESPONSIBILITIES 2 A. Basic Services 2 1. Core Forecast Grids and Web-Based Fire Weather Decision Support 2 2. Fire Weather Watches and Red Flag Warnings (RFW) 2 3. Spot Forecasts 5 4. Fire Weather Planning Forecasts (FWF) 7 5. NFDRS 8 6. Fire Weather Area Forecast Discussion (AFD) 9 7. Interagency Participation 9 B. Special Services 9 C. Forecaster Training 9 D. Individual NWS Forecast Office Information 10 1. Northwest Arizona – Las Vegas, NV 10 2. Northern Arizona – Flagstaff, AZ 10 3. Southeast Arizona – Tucson, AZ 10 4. Southwest and South-Central Arizona – Phoenix, AZ 10 5. Northern and Central New Mexico – Albuquerque, NM 10 6. Southwest/South-Central New Mexico and Far West Texas – El Paso, TX 10 7. Southeast New Mexico and Southwest Texas – Midland, TX 10 8. West-Central Texas – Lubbock, TX 10 9. Texas and Oklahoma Panhandles – Amarillo, TX 10 V. WILDLAND FIRE AGENCY SERVICES AND RESPONSIBILITIES 11 A. Operational Support and Predictive Services 11 B. Program Management 12 C. Monitoring, Feedback and Improvement 12 D. Technology Transfer 12 E. Agency Computer Systems 12 F. WIMS ID’s for NFDRS Stations 12 G. Fire Weather Observations 13 H. Local Fire Management Liaisons & Southwest Area Decision Support Committee___14 Southwest Area Fire Weather Annual Operating Plan Table of Contents VI.
    [Show full text]
  • Northwest Area Fire Weather Annual Operating Plan
    2011 Seattle Portland Medford Spokane Northwest Area Pendleton Fire Weather Boise Annual Operating ODF Salem Plan NWCC Predictive Services Table of Contents Introduction………………………………………………………………..3 NWS Services and Responsibilities……………………………………….4 Wildland Fire Agency Services and Responsibilities……………………..8 Joint Responsibilities……………………………………………….……..9 New for 2011……………………………………………………………..10 Seattle……………………………………………………………………..11 Portland………………………………………………………………..….22 Medford………………………………………………………….…….….34 Spokane…………………………………………………….……………..45 Pendleton……………………………………………………….…….…...57 Boise…………………………………………………….……………..….68 ODF Salem Weather Center………………………………………………74 NWCC Predictive Services……………………………………………….78 Plan Approval……………………………………………………………..84 Appendix A: Links to Fire Weather Agreements and Documents…….…85 Appendix B: Forecast Service Performance Measures…………………..86 Appendix C: Reimbursement for NWS Provided Training……………...87 Appendix D: IMET Reimbursement Billing Contacts…………………...88 Appendix E: Spot Request WS Form D-1……………………………….89 2 INTRODUCTION a. The Pacific Northwest Fire Weather Annual Operating Plan (AOP) constitutes an agreement between the Pacific Northwest Wildfire Coordinating Group (PNWCG), comprised of State, local government and Federal land management agencies charged with the protection of life, property and resources within the Pacific Northwest from threat of wildfire; and the National Weather Service (NWS), National Oceanic and Atmospheric Administration, U.S. Department of Commerce, charged with providing
    [Show full text]
  • Evolution of a Pyrocumulonimbus Event Associated with an Extreme Wildfire in Tasmania, Australia
    Nat. Hazards Earth Syst. Sci., 20, 1497–1511, 2020 https://doi.org/10.5194/nhess-20-1497-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Evolution of a pyrocumulonimbus event associated with an extreme wildfire in Tasmania, Australia Mercy N. Ndalila1, Grant J. Williamson1, Paul Fox-Hughes2, Jason Sharples3, and David M. J. S. Bowman1 1School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia 2Bureau of Meteorology, Hobart, TAS 7001, Australia 3School of Science, University of New South Wales, Canberra, ACT 2601, Australia Correspondence: Mercy N. Ndalila ([email protected]) Received: 24 October 2019 – Discussion started: 19 December 2019 Revised: 30 March 2020 – Accepted: 18 April 2020 – Published: 27 May 2020 Abstract. Extreme fires have substantial adverse effects on ciated with pyroCb development. Our findings have implica- society and natural ecosystems. Such events can be associ- tions for fire weather forecasting and wildfire management, ated with the intense coupling of fire behaviour with the at- and they highlight the vulnerability of south-east Tasmania mosphere, resulting in extreme fire characteristics such as py- to extreme fire events. rocumulonimbus cloud (pyroCb) development. Concern that anthropogenic climate change is increasing the occurrence of pyroCbs globally is driving more focused research into these meteorological phenomena. Using 6 min scans from a nearby 1 Introduction weather radar, we describe the development of a pyroCb during the afternoon of 4 January 2013 above the Forcett– Anthropogenic climate change is increasing the occurrence Dunalley fire in south-eastern Tasmania. We relate storm de- of dangerous fire weather conditions globally (Jolly et al., velopment to (1) near-surface weather using the McArthur 2015; Abatzoglou et al., 2019), leading to high-intensity forest fire danger index (FFDI) and the C-Haines index, the wildland fires.
    [Show full text]
  • Fire Weather Product & Service Guide
    FIRE WEATHER PRODUCT & SERVICE GUIDE FOR MUCH OF VERMONT & NORTHERN NEW YORK NATIONAL WEATHER SERVICE BURLINGTON, VT 2021 (Updated 3/10/2020) Prepared by: Eric Evenson Fire Weather Program Leader National Weather Service Burlington, VT 1 TABLE OF CONTENTS Section Page NWS Burlington, VT Fire Weather Product & Service Guide Overview .......................... 3 NWS Burlington Contacts ................................................................................................ 4 Digital Forecasts and Services ........................................................................................ 5 Fire Weather Planning Forecast (FWF) ........................................................................... 6 NFDRS Point Forecasts (FWM) .................................................................................... 10 Red Flag Program (RFW) ............................................................................................. 12 1. Red Flag Event/State Liaison.............................................................................. 12 2. Red Flag Criteria ................................................................................................ 13 3. Fire Weather Watch ............................................................................................ 14 4. Red Flag Warning ............................................................................................... 14 5. Special Weather Statement ................................................................................ 15 6. Fire Weather Area
    [Show full text]
  • Extending the Haines Index
    The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Atmospheric Stability Environments and Fire Weather in Australia – extending the Haines Index Graham A. Mills and Lachlan McCaw CAWCR Technical report No. 20 March 2010 Atmospheric Stability Environments and Fire Weather in Australia – extending the Haines Index Graham A. Mills 1,2 and Lachlan McCaw 2,3 1Centre for Australian Weather and Climate Research 2Bushfire Cooperative Research Centre 3 Department of Environment and Conservation, Manjimup. Western Australia CAWCR Technical Report No. 020 March 2010 ISSN: 1836-019X National Library of Australia Cataloguing-in-Publication entry Title: Atmospheric Stability Environments and Fire Weather in Australia – extending the Haines Index [electronic resource] / Graham A. Mills and Lachlan McCaw. ISBN: 978-1-921605-56-7 (pdf) Series: CAWCR technical report ; 20. Enquiries should be addressed to: Dr Graham A. Mills Centre for Australian Weather and Climate Research: A partnership between the Bureau of Meteorology and CSIRO GPO Box 1289, Melbourne Victoria 3001, Australia [email protected] Copyright and Disclaimer © 2010 CSIRO and the Bureau of Meteorology. To the extent permitted by law, all rights are reserved and no part of this publication covered by copyright may be reproduced or copied in any form or by any means except with the written permission of CSIRO and the Bureau of Meteorology. CSIRO and the Bureau of Meteorology advise that the information contained in this publication comprises general statements based on scientific research. The reader is advised and needs to be aware that such information may be incomplete or unable to be used in any specific situation.
    [Show full text]
  • Weather Forecasts on Forest Service Radios
    Weather Forecasts on Forest Service Radios Columbia Dispatch broadcasts the weather forecasts for the Forest Service on the Radio’s, at two times a day, about 10 am and I think 4 or 4:30. If you’ve been scanning your radio, at these times, you’ve heard the weather forecast. It gets repeated over different repeaters, so you hear the forecast two or three times (and with varying levels of signal quality, too). The information is really good weather forecast, but there are terms they use that are not in our standard weather forecasts you get on the 6 o’clock news. They also refer to zones, and I never could figure out if the forecast was for where I was or somewhere else. Here’s the cheat sheet on the info. The map is included for details, but essentially, almost all the PCT on Mt Hood area (south of the Columbia) is in Zone 607, with East side of Mt Hood-Barlow Pass-Frog Lake boarding into Zone 639 and Pinheads and Olallie Lake bordering into Zone 610. For the most part, any weather for Zone 607 would be applicable, given the geography and weather patterns. The PCT on the North side of the Columbia is in Zone 660. (There is a map for all of Oregon, if you are interested, I can send you that one, too.) A few terms they use in the weather: • LAL – Lightening Activity Level – see below • Haines Index – see below Lightning Activity Level: The chart listed below will be used to forecast Lightning Activity Level (LAL): • LAL = 1 No Thunderstorms • LAL = 2 Isolated Thunderstorms • LAL = 3 Isolated Thunderstorms (Increased Confidence/Threat) • LAL = 4 Scattered Thunderstorms • LAL = 5 Numerous Thunderstorms • LAL = 6 Scattered (But Exclusively Dry) Thunderstorms Haines (1988) developed the Lower Atmosphere Stability Index, or Haines Index, for fire weather use.
    [Show full text]
  • I the University of Nevada, Reno Examining Atmospheric And
    i The University of Nevada, Reno Examining Atmospheric and Ecological Drivers of Wildfires, Modeling Wildfire Occurrence in the Southwest United States, and Using Atmospheric Sounding Observations to Verify National Weather Service Spot Forecasts A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Atmospheric Sciences by Nicholas J. Nauslar Dr. Timothy J. Brown/Dissertation Advisor December, 2015 ii ©Copyright by Nicholas J. Nauslar 2015 All Rights Reserved iii THE GRADUATE SCHOOL We recommend that the dissertation prepared under our supervision by NICHOLAS J. NAUSLAR Entitled Examining Atmospheric And Ecological Drivers Of Wildfires, Modeling Wildfire Occurrence In The Southwest United States, And Using Atmospheric Sounding Observations To Verify National Weather Service Spot Forecasts be accepted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Timothy J. Brown, Advisor Michael L. Kaplan, Committee Member John F. Mejia, Committee Member John D. Horel, Committee Member Peter J. Weisberg, Graduate School Representative David W. Zeh, Ph. D., Dean, Graduate School December, 2015 i Abstract This dissertation is comprised of three different papers that all pertain to wildland fire applications. The first paper performs a verification analysis on mixing height, transport winds, and Haines Index from National Weather Service spot forecasts across the United States. The final two papers, which are closely related, examine atmospheric and ecological drivers of wildfire for the Southwest Area (SWA) (Arizona, New Mexico, west Texas, and Oklahoma panhandle) to better equip operational fire meteorologists and managers to make informed decisions on wildfire potential in this region. The verification analysis here utilizes NWS spot forecasts of mixing height, transport winds and Haines Index from 2009-2013 issued for a location within 50 km of an upper sounding location and valid for the day of the fire event.
    [Show full text]
  • NFDRS Introduction
    A Publication of the National Wildfire Coordinating Group Gaining an Understanding Sponsored by United States Department of Agriculture of the United States Department of the Interior National Fire Danger Rating System National Association of State Foresters PMS 932 _________________ July 2002 NFES 2665 Gaining an Understanding of the National Fire Danger Rating System A publication of the NWCG Fire Danger Working Team Compiled by Paul Schlobohm and Jim Brain This document was made possible with the help of Larry Bradshaw, Jeff Barnes, Mike Barrowcliff, Roberta Bartlette, Doug Bright, Gary Curcio, Brian Eldredge, Russ Gripp, Linnea Keating, Sue Petersen, Kolleen Shelley, Phil Sielaff, and Paul Werth ______________________________________________________________________________ The NWCG has developed this information for the guidance of its member agencies and is not responsible for the interpretation or use of this information by anyone except the member agencies. The use of trade, firm or corporation names in this publication is for the information and convenience of the reader and does not constitute an endorsement by the NWCG of any product or service to the exclusion of others that may be suitable. ______________________________________________________________________________ Additional copies of this publication may be ordered from: National Interagency Fire Center, ATTN: Great Basin Cache Supply Office, 3833 South Development Avenue, Boise, Idaho 83705. Order NFES # 2665 ______________________________________________________________________________ This document is also available in PDF format at the following website: http://www.nwcg.gov PREFACE Gaining an Understanding of the National Fire Danger Rating System is a guide explaining the basic concepts of the National Fire Danger Rating System (NFDRS). This guide is intended for everyone in fire and resource management who needs an elementary understanding of NFDRS, including managers, operations specialists, dispatchers, firefighters, and public information specialists.
    [Show full text]