U. S. DEPARTMENT OF COMMERCE CHARLES SAWYER, Secretary WEATHER BUREAU P. W. REICHELDERFER, Chief CLB4ATOLOGICAL DATA NATIONAL SUMMARY FEBRUARY 1950 Volume I WAAMOMM ILMO C 0 N T E N T S SURFACE DATA Page General Summary of Weather Conditions duringFebruary 1950-- 1 Condensed Climatological Summary - States ------------------ 3 Climatological Data - Weather Bureau Stations -------------- 4 Heating Degree Days ---------------------------------------- 8 Severe Storms ---------------------------------------------- 9 River Stages and Floods for February195O ------------------- 16 Flood Stage Report ----------------------------------------- 19 UPPER AIR DATA Radiosonde Data -------------------------------------------- -22 Pilot Balloon Data ----------------------------------------- 25 Rawin Data ------------------------------------------------- 26 SOLAR RADIATION DATA Solar Radiation Intensities -------------------------------- 27 Blue Hill Data --------------------------------------------- 27 Daily and Weekly Averages of Solar Radiation --------------- 28 CHARTS I-XI NOTE.--This publication contains all of the climatic data form- erly printed in the MONTHLY WEATHER REVIEW. SUBSCRIPTION PRICE: Monthly and annual, 15 cents per copy;year- ly subscriptionincluding monthly and annual issues,$1.50.Checks, postal notes, and money orders should be made payable to the "Treasurer of the United States."Remittance and correspondencere- garding subscriptions should be sent to "Superintendent of Docu- ments, Government Printing Office, Washington 25, D.C." WEATHER BUREAU DEPARTMENT OF COMMERCE F. W. REICHMMYER, ChW CHARLES SAWYER, SetarY CUMATOLOGICAL DATA NATIONAL SUMMARY Volume I No. 2 FEBRUARY 1950 GENERAL SUMMARY OF WEATHER CONDMONS The January weather pattern of severe cold in the North- With the exception of a few western areas temperatures west, abnormal warmth east of the Mississippi River, and during the second week averaged above normal over the heavy precipitation in most of the area from the Mississippi entire country. In the Northwest there was considerable Valley to the Appalachians continued through the first week thawing which caused muddy roads and some local flooding of February. In fact, the most severe weather of the winter in Washington. Precipitation was general over the West occurred in the Northwest during this period. Many stations early in the week and occurred daily in Washington and Oregon, in the eastern portions of Washington and Oregon registered being quite heavy in the coastal regions. During a storm their lowest temperatures of record, weekly averages were on the 6th and 7th Salt Lake City, Utah recorded 1.43 inches below zero at some stations, and departures ranged from of precipitation in 24 hours, a new record. Precipitation 30' to 35' below normal. At Cut Bank, Montana frost had was frequent east of the Great Plains, with heavy rains in penetrated to a depth of 7 feet, and many cities in northern the Ohio and lower Mississippi Valleys further aggravating Montana and eastern Washington experienced difficulties the flood situation. On the Ilth and 12th much thunderstorm with frozen water mains. With low temperatures and addi- activity and a number of tornadoes occurred in south-central tional light to heavy snowfall, the heavy snowcover at the areas. The unusually warm weather in the South caused end of January was maintained from Washington to the Great abnormal advancement of vegetation, especially fruit. Lakes. Some farmers rer.Pained isolated in North Dakota, Widespread glaze which occurred near the end of the second schools were still closed in parts of Washington, and many week in the Northeast and Midwest continued during the first roads were snow-blocked throughout the area. few days of the 3d week. A number of deaths and many During the first 2 or 3 days of the month it was rather injuries resulted from accidents due to the ice. Damage to cold in the Southwest, and subzero temperatures were recorded power and communication lines and trees amounted to many in the Great Plains as far south as Kansas, northern Missouri, millions. The ice was as much as 2 inches thick in some of and Illinois. However, temperatures rose throughout the the worst areas. West the latter part of the first week, reaching above-normal The temperature pattern was reversed during the last half levels in the Great Plains. of the month. Cold air masses which had formerly stalled East of the Mississippi temperatures for the first week between the Great Plains and the Appalachians began to averaged above normal, especially in the southern portion, move across the eastern states holding temperatures to although the first of the week was somewhat cooler than normal levels or considerably below, while persistently normal in the Lake Region. In the southern states daily above-normal temperatures prevailed in the West. Plus departures ranged from 5* to over 200. Precipitation At the beginning of the third week heavy rains over the Ohio was negligible in the southern Rocky Mountain States, parts and lower Mississippi Valleys caused flooded -streams to of the Midwest, and most of the Lake Region. Heavy precipi - rise still further. Light to locally heavy snowfall in north- tation fell in the Pacific States and heavy rain which fell in ern areasfromNewEngland to Minnesota blocked many roads, a broad belt from Texas to New England caused a continua- and miKed rain and snow that fell along the northeastern coast tion of flooding along many streams in the Ohio and lower made highways extremely slippery. About the middle of the Mississippi Valleys. Glaze occurred in several areas, but week a cold air intrusion brought below-freezing tempera- was especially-severe in northern Arkansas and northern tures to the central Gulf Coast on the 17th and to the Ever- Texas. glades region of southern Florida on the 18th. - 1 - GENERAL SUMMARY OF WEATHER CONDMONS-Continued FEBRUARY 1950 A second cold air mass, accompanied by blizzard condi- in parts of Arizona and New Mexico. This was the coldest tions began moving into north-central areas on the 17th. week of the winter in the northeastern quarter of the coun- Light snow, strong winds, and subzero temperatures ac- try, with minus temperature departures ranging up to 140 companied its advance across the Lake Region, and by the or more at a number of stations in the Lake Region. Tempera - end of the week below-freezing minima extended almost to tures were above normal elsewhere, with departures rang- the Gulf. In the far West mostly fair weather and much- ing up to 10' in the Southwest and up to 15' on the eastern above normal temperatures, which reached record high slopes of the northern Rockies. levels in Arizona, removed the snow from most agricultural Average temperatures for the month were above normal, valleys except in the extreme north. except in a few north-central areas, the extreme North- During the last week temperatures were normal in the east, and a portion of the State of 'Washington where slight lower Great Plains and the far West, but the weather was deficiencies occurred. The greatest monthly excessaf cold and windy east of the Mississippi River. Precipitation temperature was in the northern Rockies and lower Great was again heavy in the lower Ohio and Mississippi Valleys, Plains where plus anomalies ranged up to more than 10*. resulting in continued flooding in southern Indiana and Ohio, Monthly totals of precipitation were generally below normal southeastern Missouri, and parts of Arkansas. Light to in most of the area west of the Great Plains, most extreme locally heavy snow fell north of the Ohio Valley, and a belt north-central areas, and the area south and east of a line of freezing rain, which extended from southern Missouri joining northern Virginia with New Orleans, La. The driest into Ohio, caused considerable damage to overhead wires in areas were in the western portion of the lower Great Plains the latter State. and in the extreme Southeast where a nunber of stations re- On the 23d cold air brought below-freezing minima almost ceived only 10 percent or less of their normal precipita- to the Gulf, and again near the end of the month freezing tion. The greatest totals were accumulated in a belt com- temperatures extended deep into the South and subzero prising the lower Ohio Valley, the central Mississippi Valley, temperatures were recorded in portions of the Ohio Valley. most of Arkansas, and a portion of east Texas where totals On the 25th I to 3 inches of snow fell in a belt extending were twice the February normal amounts. from southern Indiana and Ohio across West Virginia and north- At the end of the month farm activities were moving at a ern Virginia to the Atlantic Coast. Snow fell frequently normal pace in the South, but were much restricted in the in north-central areas, and drifting new snow blocked roads northeastern quarter of the country due to cold, wet weather. in northeastern Montana. Mild temperatures prevailed west Small grains were mostly satisfactory, and oat seeding pro- of the Continental Divide and precipitation was generally gressed in the lower Great Plains. Pastures were good in limited to occasional light, scattered showers, except fre- the South and were beginning to grow in the far West and quent moderate to heavy showers in western Washington Southwesf. Moisture was badly deficient in the southern por- and Oregon, and light to moderate showers on 2 or 3 days tion of the western Great Plains. WINTER (December-February), 1949-50 Average winter temperatures were below normal in the a large part of the northern Great Plains and all areas west- Pacific States and in northern areas west of the Great Lakes. ward to the Pacific coast. Minus departures were as much as 6' in the area from Precipitation was much above normal in the Ohio and central central Washington eastward through most of North Dakota, Mississippi Valleys for each of the three winter months, but ranging up to 10' in north-central Montana. Elsewhere much below in the Southeast and in the southern portion of over the country averages were above normal, with plus the western Great Plains.