MONTHLY WEATHER DATA AND OBS - WESTMONT 1.1W PA MARCH 2011 OBSERVER NATE MULLINS Special Observations: F=fog, T=thunder, H=hail, S=sleet, G=glaze, DW=damaging winds Observation time for this station is midnight (Eastern US). Temperature, °F Precipitation, In. Liquid Solid 7am 24-hour At Rain Snow/ Snow Date Max Min Obs Equiv Ice Depth Special Obs. 1 43 20 28 2 45 17 17 3 37 10 27 4 46 26 40 5 52 39 49 .29 6 49 26 26 .73 2.0 F,S 7 36 19 26 2 8 44 20 36 1 9 37 31 37 .52 1.0 T F,S 10 48 33 33 2.45 T F,DW 11 33 29 32 .28 2.3 1 S 12 56 30 41 2 13 41 32 32 T T 14 44 30 33 T T T 15 46 28 35 .13 F 16 43 35 39 .10 F 17 61 38 49 18 70 49 50 T 19 50 33 33 20 54 27 44 T T 21 68 40 46 .26 T 22 51 39 40 .10 23 48 36 44 1.27 F,T,H 24 44 23 23 .09 0.9 T F 25 32 18 26 T 0.1 T 26 37 17 27 T 0.2 T 27 38 22 23 28 37 16 25 29 43 19 32 30 38 25 31 .24 2.0 F,S 31 33 31 31 .21 1.0 2 F,G AVG/SUM 45.3 26.7 34.0 6.67 9.5 0.3 <-- mean EXT 70 10 50/17 2.45 2.3 2 Date 18 3 18/2 10 11 31* *=Also occurred on earlier dates Miscellaneous Stats Mean Monthly Temperature: 36.5°F (-0.9°F) Year precipitation to date: 15.12" (+4.02") Monthly Precipitation Departure: +2.80" Season snowfall to date: 120.1" Number of days with: Fog 9 Sleet 4 Glaze 1 Thunder 2 Hail 1 Damaging Winds 1 DETAILED OBSERVATION NOTES 1: Partly cloudy, cold early, breezy, seasonable temps. 2: Partly cloudy, seasonable temps but gusty NW winds which made it blustery. Temperatures dropped off quickly this evening to a low of 17 F by midnight. 3: Mostly clear/sunny and cold this morning low 10 F. Sunny but breezy and a bit blustery with high of 37. Winds were opposite yesterday - from the SE. 4: Variably cloudy and a bit milder, occasional breezes from the south. 5: Mild this morning with temperatures rising overnight into the mid 40s and occasional wind gusts from the south. Occasional light rain and showers through the evening .29" fell. WINTER RETURNS 6: Mild overnight with occasional rain, becoming steady during the morning hours and turned to sleet then wet snow as temperatures dropped below freezing during the afternoon. Gusty winds shifted from S to N by evening, snow tapered off by 9pm 2.0" fell .73" of precip. 7: Becoming mostly clear overnight. Sunny but chilly today with light & variable winds. 8: Clear & cold overnight with heavy frost. Partly cloudy with seasonable temperatures and breezy conditions with winds from SE. LIGHT MIX TO HEAVY RAIN 9: Breezy overnight with a brief period of light snow prior to daybreak. A mix of rain, snow and sleet through much of the day with gusty SE winds. Precipitation was light but steady with about 1.0" of slushy snow/sleet accumulation, mainly on grassy surfaces. All rain during the evening hours, light to occasionally moderate .52" fell. Some light fog also. 10: Steady, mostly light rain overnight .43" by 7am with rain tapering to occasional light showers. Drenching downpours this afternoon and evening with the heaviest rains from about 3:30 to 4:30 and especially 6:30-7:30 with nearly an inch of rain within that hour. Also strong W winds blew down part of the wooden fence out back. Temperatures dropped into the mid 30s with rain mixing with wet snow late this evening 2.45" of rain fell by midnight with snow starting to stick. Some local flash flooding from the heavy rains. SOME SNOW/SLEET 11: A period of snow shortly after midnight ending around 2 am. 1.0" accumulation. Windy with west winds gusting 35+ mph. Periods of light snow and sleet throughout the day and breezy with temperatures steady around 30. 2.3" of snow/sleet accumulation. 12: Steady temperatures overnight then warming quickly with gusty SW winds and partly cloudy skies. Mild high 56 F which quickly melted the snow. 13: Becoming overcast with occasional flurries and temperatures falling slowly through the 30s during the day, windy and a bit blustery. 14: Cloudy this morning with flurries, only a very light dusting, then cleared to partly cloudy skies with light variable winds and a bit milder. 15: Fair to partly cloudy overnight, mostly cloudy during the day with strong SE breezes and light rain & drizzle beginning around 5pm with light fog also. 16: Foggy overnight with a period of light rain, temperatures steady in the mid 30s. Low clouds, patchy fog & occasional drizzle. Temperatures rose slightly this evening. 17: Partly to mostly sunny and mild, pleasant day, light SW breezes and a high of 61. 18: Very windy and mild all day and evening with strong SW wind gusts 40+ mph with variable clouds and a few sprinkles late this evening. 19: Partly to mostly sunny and breezy with temperatures gradually dropping through the day. 20: Partly sunny becoming mostly sunny with moderate breezes from S and a fair somewhat mild evening. THUNDERSTORMS 21: A couple of brief pre-dawn thunderstorms, followed by occasional brief showers through the morning. Very mild high 68 F with gusty W winds. More thunderstorms passed just SW of the station this evening. Peepers heard for the 1st time this season. 22: Partly to mostly cloudy, breezy and somewhat blustery at times. All cloudy by 5pm with rain late this evening .10" by midnight. HEAVY RAIN - SEVERE THUNDERSTORMS & TORNADOES NEARBY 23: Periods of light rain overnight, becoming moderate to heavy during the mid-morning with patchy dense fog developing and chilly temperatures, breezy. A wild evening began about 5pm as a tornado warning went into effect for Johnstown. The t-storm brought pea-sized hail but nothing severe and no tornadoes. A 2nd storm about 6pm prompted another severe storm warning but again only heavy rain & pea-sized hail were noted. Areas just to our west and south really got hammered. Tornadoes were reported in Greensburg to the west, and large hail up to tennis ball size battered parts of Somerset Co. just to our south. WINTER RETURNS AGAIN 24: Becoming colder overnight with light snow this morning 0.4" by 8am 0.9" by ~ noon with snow tapering off. Mostly cloudy, breezy & blustery - mostly clear after sunset, cold. 25: Cold this morning low 18 with snow flurries. Skies cleared to partly sunny but still cold high only 32 F with light W winds. 26: A brief period of light snow this morning 0.2" then rapid clearing, snow was very dry and sublimated when the sun appeared, so no measurable water. Still chilly high 37 F. 27: Another fair but chilly day and evening with brisk north winds and a high of 38. 28: Mostly sunny, breezy & chilly, low 16 high only 37 29: Again mostly sunny but cold, breezy at times. Partly cloudy after sunset. MORE WINTER WEATHER - MIXED PRECIP 30: Cloudy, light snow slowly developed this afternoon and mixed with some sleet and light freezing rain making a rather slushy mess, ended by 10pm 2.0" snow/sleet, .24" precip 31: Light snow & rain/freezing rain mix overnight, another 0.6" snow/ice and .11" precip. Overcast and cold with low clouds & fog, light snow resumed by mid-evening. MONTHLY SUMMARY March is supposed to come in like a lion and leave like a lamb, but this month was quite opposite. Temperatures followed the usual March trend, starting off chilly, then becoming rather balmy, with highs reaching 70 by the 18th. It appeared winter was over and spring was on its way in. Instead, winter made another return, with a very cold final week and the month closing out with wet snows on the final two days. It was a March full of madness that included heavy rains, flooding, snow and ice, dense fog, damaging winds and strong to severe thunderstorms with hail. In a nutshell, March's weather was pretty wild. March began cold and fair, then seasonal temperatures persisted for most of the first half. The 3rd week was quite mild, with 6 of the month's 8 50+ days occurring consecutively from the 17th-22nd. However, following this mild stretch, the final week was cold, with 6 of 7 days only in the 30s, one of which failed to reach above freezing, and 4 lows in the teens, dragged temperatures slightly below normal. The weather pattern was quite active, with two major storms affecting the area during the first two weeks. The first storm on the 5th-6th brought over an inch of precipitation and 2" of snow on the back side. The second storm brought well over 3" of precipitation from the 9th-11th, with torrential downpours on the evening of the 10th bringing the day's total to 2.45" and causing some local flash floods. Temperatures warmed up, with several more systems affecting the area. Back-to-back cold fronts brought thunderstorms on the 21st and 23rd. On the evening of the 23rd, a tornadic supercell prompted numerous warnings for Johnstown, but the storm veered slightly south and weakened. It brought large hail just south of town, up to the size of tennis balls, and a tornado touched down near Greensburg in Westmoreland County to our west. Temperatures more like late January than late March returned for the final week, with mostly fair skies, until a developing Nor' Easter brought light snows to the area on the final two days.