MONTHLY WEATHER DATA AND OBS - WESTMONT 1.1W PA APRIL 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 37 30 31 .19 1.7 3 F 2 41 30 34 .31 2.8 3 F 3 46 33 42 .01 2 T 4 71 41 56 .89 T F,T 5 56 31 31 .35 T F,S 6 56 31 42 .01 T T 7 65 40 45 8 45 37 37 .77 F 9 46 37 43 F 10 80 43 58 11 78 54 54 .40 T 12 54 42 42 .99 F 13 45 40 40 .14 F 14 66 34 51 15 64 40 49 16 52 42 43 1.00 F,DW 17 54 34 52 .07 18 70 39 54 19 60 45 53 .71 F,T,H 20 69 52 42 T 21 53 37 40 22 41 34 41 .54 F 23 74 41 60 .15 T 24 68 56 56 .05 25 83 56 61 .09 T 26 80 56 58 .41 F,T 27 83 54 61 .27 F,T 28 64 52 53 .27 T 29 54 41 43 .22 30 64 36 53 AVG/SUM 60.6 41.3 47.5 7.84 4.5 0.3" avg EXT 83 30 61/31 1.00 2.8 3 Date 27* 2* 27*/5* 16 2 2* *=Also occurred on earlier dates Miscellaneous Stats Mean Monthly Temperature: 51.0°F (2.6°F) Year precipitation to date: 22.96" (+8.05") Monthly precipitation departure: +4.03" Season snowfall to date: 124.6" Number of days with: Fog 13 Sleet 1 Thunder 9 Hail 1 Damaging Winds 1 DETAILED OBSERVATION NOTES APRIL...OR FEBRUARY??? 1: Light snow overnight another 0.8" since midnight 1.2" since 9pm with light fog and low clouds. More snow showers this afternoon nearly another inch accumulated before the sun appeared and melted much of the snow. Partly cloudy after sunset. 2: Steady snow commenced again prior to sunrise and continued intermittently through the morning, tapering to flurries by noon, then variably cloudy with a few brief rain and snow showers this evening, breezy & blustery, 2.8" of snow .31" precip. 3: Partly sunny, milder, most of the snow melted. Became overcast by mid-afternoon with thunderstorms by-passing us north & south, thunder & lightning but only .01" rain. MILDER - RAIN/THUNDERSTORMS 4: Mostly cloudy, breezy & mild high 71, frequent showers and thunderstorms late this afternoon & through the evening, wind gust to 54 mph @ airport from 6:30pm storm, a severe storm warning but not severe here, periods of rain continued overnight. 5: Occasional light to moderate rain overnight, breezy with falling temps. Rain mixed with and changed to intermittent snow/sleet this morning. Several times there was a slushy coating on grass and elevated surfaces but it was not measurable. 6: Flurries overnight & this morning, sprinkles & flurries then mostly cloudy and milder in the afternoon as a large system passed to the north. Gusty west winds. 7: Mostly cloudy early, becoming partly sunny and mild with NE breezes. MORE RAIN - COOL 8: Light rain and drizzle overnight and this morning, patchy fog, chilly, occasionally breezy, periods of rain during the afternoon, drizzle after dusk, .77" of rain fell. 9: No rain but heavy overcast and haze/fog all day and quite cool high only 46. VERY WARM - THEN COOL & WET AGAIN 10: Partly to mostly sunny, breezy and dramatically warmer high 80 F. 11: Mild overnight, variable clouds, strong SW to W breezes, a brief thunderstorm about 2pm, then periods of rain showers through the evening and becoming cooler. 12: Occasional light rain overnight and through the morning, periods of rain heavy at times late this afternoon and evening .99" of rain for the day. This was another chilly raw day with temperatures dropping into the 40s and winds from the NE. 13: Periods of light rain & drizzle overnight and through the morning with patchy fog. Overcast, cool & breezy PM. 14: Cool overnight, frost in some areas, then a rare sunny, mild, breezy, pleasant day. 15: Mostly sunny & pleasant, then increasing clouds with strong SSE winds this evening. VERY WINDY - WET - CHILLY 16: Occasional rain showers began overnight and very windy with a SSE wind gust to 54 mph. Scattered tree damage and power outages were reported throughout the area. More soaking rains early-mid afternoon with occasional evening showers after a brief break in the clouds & fog. 1.00" of rain fell today. 17: Continued very windy overnight with occasional light showers another .07". Mostly cloudy and blustery with west winds gusting to 40 mph, a few sprinkles. 18: Variably to mostly cloudy, breezy & mild high 70 F. 19: Occasional rain showers beginning around 7am with patchy fog, a thunderstorm 5-6pm and a very brief storm at 8:55pm only 5 minutes of rain, sharp lightning and pea- sized hail but little wind despite a severe storm warning. Radar showed possibly larger hail and even some rotation in the area, but there were no severe reports. 20: Mild and breezy overnight, another large system this time evaporated as it approached from the west, only a bit of drizzle. Mild, partly cloudy, very windy. 21: Mostly sunny (for once) and continued breezy and a bit cooler, fair cool evening. MORE COLD RAINS - THEN WARM - SCATTERED SHOWERS/STORMS 22: Clouds moved in overnight, light SW breezes. Light rain began around 10:30am, with light to moderate rain showers continuing on and off through the day and tapering to drizzle this evening. Another very chilly raw day high only 41 F. 23: Some brief showers overnight with some lightning & thunder, couple AM showers, then becoming variably cloudy and mild high 74 F with gusty SW winds. Clouds came in quickly this evening but a large cluster of storms passed just to our south. 24: A brief shower at 9:30am, then partial clearing, mostly cloudy PM with light SW winds, some threatening skies but only a few sprinkles. 25: Mild overnight again, a brief light AM shower then variable clouds and very warm high 83 F with light SW winds, a couple of brief late evening showers, the first with some thunder. Only .09" rain despite a radar estimate of a half-inch. MANY SEVERE THUNDERSTORMS - WESTMONT DODGES MAJOR BULLETS 26: Partly cloudy with valley fog early, multiple PM severe thunderstorms prompted warnings but every storm seemed to just miss or clip us, we did not receive any hail or damaging winds and had far less rain than most areas around us. Winds were clocked at 61 mph at the Johnstown airport 6 miles to our east from the 1st severe storm, and the 2nd severe storm very narrowly missed to the west & north. I drove through this storm atop Chickaree Ridge on US 22 and it was one of the wildest storms I've ever seen. Clouds were black and green with strong rotation, then buckets of rain and large hail up to golf ball size, intense winds & constant lightning. Some flash flooding especially in the northern part of the county, and further south, a tornado possibly touched down near my old hometown Cumberland MD. So far Westmont has dodged every severe storm in 2011, quite opposite from 2010. 27: Another unseasonably warm day with strong S winds gusting to 40 mph. Less windy and more cloudy this evening, another cluster of big storms blew up to our north but missed us here, an isolated storm at 10:45pm dumped .25" of rain in 5 minutes. 28: Mild thunderstorms early overnight between midnight-2am not much rain and nothing severe as was predicted. Again we dodged the bullet, as areas to our east around Harrisburg were again pounded with severe storms & flooding rains. Became windy and partly to mostly sunny during the day with cooler temperatures in the 60s. 29: Mostly cloudy, cool & blustery with temperatures in the 40s and more rain showers on and off through the day .22" fell, west winds gusted 30+ mph. 30: Clearing overnight and cool low 36, then a pleasant day with a high of 64, sunny, near calm winds, skies became mostly cloudy by mid-afternoon. MONTHLY SUMMARY April was a warm and extremely active weather month. It brought a record number of tornadoes to the US, especially in the southeast and midwest. A huge outburst of tornadoes struck many parts of the midwest into PA on the 14th-16th, a terrifying twister ravaged the St. Louis airport on the 22nd, and the 26th-28th brought the 2nd deadliest tornado outbreak ever to the south, the worst weather disaster in the US since Hurricane Katrina devastated the Gulf Coast in 2005. On the 26th, I drove through the most severe thunderstorm I have seen since the Frostburg Tornado in 1998. The persistent unsettled weather pattern led to 9 days with thunderstorms, many with multiple thunderstorms, unquestionably the most number of thunderstorms I have ever seen in April. While many severe thunderstorms, all accompanied by warnings, flirted with Westmont, our station escaped unscathed compared to some nearby parts of Cambria County and the state of PA. 7 tornadoes touched down in Pennsylvania during April. There were also an unusual number of reports of wind damage, large hail and flooding. In addition to this being one of the stormiest Aprils on record, it was also one of the wettest. 21 days had measurable precipitation. There were very frequent moderate precipitation events throughout April, which started off looking and feeling like February, given that 4.5" of snow fell the first two days. The rest of the measurable precipitation fell as rain. While we dodged the major flooding bullet as well, some parts of the state, especially over north-central areas down the Susquehanna River Valley, had their wettest April on record with over 10 inches of rain in areas like Williamsport and Harrisburg. Severe floods hit the midwest and many southern states. At this location, 7.84" precipitation fell - more than twice the average of 3.81". Slightly different storm tracks, and we could have broken 1948's April record 7.94". My CoCoRaHS station with a 7am obs time tied this record with .10" carried from 3/31, our 4th recent monthly precip record (Aug 07 10.48", Dec 07 6.88" then Dec 08 8.80"). Surprisingly, April ended up rather warm, with moderately above normal temperatures, especially in the low temperature department. As is often the case this time of year, the thermometer was all over the place. We went from a high of 37 on the 1st to a summer-like 83 on the 25th and 27th. 4 days had highs in the 80s, 4 in the 70s, 8 in the 60s, 7 in the 50s, 6 in the 40s and 1 in the 30s - quite a spread. Lows didn't vary nearly as much, and the month's low was a very modest 30, with only 4 readings below freezing, all in the first 6 days. 13 lows were in the 30s, 10 in the 40s and 7 in the 50s. Overall the temperature trend was typical for April - chilly early then finishing with some balmy weather, following a warm-frontal passage on the 22nd, which had a high of only 41. On the other hand, highs reached 80 as early as the 10th, and this was following a max of only 46 the previous day. The large temperature swings, unusual number of thunderstorms and days with rain, a record-shattering number of destructive and deadly US tornadoes, and record amounts of rain in many areas had nearly everybody talking about the weather in a very wild and tragic weather month.