MONTHLY WEATHER DATA AND OBS - WESTMONT 1.1W PA AUGUST 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 91 62 71 T T 2 90 65 70 .01 3 74 67 71 .32 F 4 91 68 70 .10 5 78 68 68 .13 6 78 67 70 .52 F 7 79 69 72 1.08 F,T 8 84 64 64 .05 T 9 76 63 67 1.69 F,T 10 78 63 63 11 81 55 60 12 85 48 63 13 82 58 65 14 76 63 63 .97 F,T 15 68 61 63 .25 F,T 16 84 61 62 17 88 53 66 18 87 59 64 19 90 57 58 .22 F,T 20 85 53 66 .01 F 21 86 60 61 .42 T 22 75 56 56 23 84 46 58 24 81 53 69 25 77 63 63 1.07 F,T 26 83 56 66 27 79 64 66 .06 28 75 57 57 T 29 73 49 55 30 84 46 61 31 87 55 64 AVG/SUM 81.6 59.0 64.3 6.90 0.0 - EXT 91 46 72/55 1.69 - - Date 4* 30* 7/29 9 - - *=Also occurred on earlier dates Miscellaneous Stats Mean Monthly Temperature: 70.3°F (+1.3°F) Year precipitation to date: 40.52" (+7.23") Monthly precipitation departure: +2.80" (normal August 4.10") Season snowfall to date: 0.0" Number of days with: Fog 9 Thunder 9 DETAILED OBSERVATION NOTES 1: Partly cloudy, hot & humid high 91. Scattered thunderstorms north & south of the station but all we got were a few sprinkles. 2: Sunny AM, increasing PM clouds, hot & humid again, very light rain showers late this evening. 3: Occasional light rain or drizzle overnight, drizzle and occasional rain showers much of the day, much cooler high 74, patchy PM fog. 4: Couple brief showers overnight, partly cloudy, hot & humid with light winds becoming SE. 5: Variable clouds, a couple of brief bursts of rain between 2-3pm, cooler, light variable wind. RAIN, THUNDERSTORMS & COOLER TEMPS 6: Increasing clouds again, occasional showers, briefly heavy @ times, through the morning and early afternoon with cooler temps. Partial clearing with haze and light fog this evening. 7: Intense thunderstorm overnight 2:30-3:30am. Rain was brief but very heavy with 1.01" in only 15 minutes, .71" in a mere 5 minutes and a peak rainfall rate of 12.52"/hr. Mostly cloudy, AM fog, very hazy/humid with a couple of brief showers, partly cloudy PM, light winds. 8: A brief shower overnight, heavy AM overcast, partial PM clearing, multiple thunderstorms passed north & south of this station this afternoon & evening but no measurable rain fell. 9: Thunderstorms early this morning from 5-6:30am with most of the .87" of rain falling in only 15 minutes beginning around 6am. Some fog, then variably cloudy, another heavy thunderstorm downpour shortly before 1pm with again about .75" in only 15 minutes, a very brief storm @ 4:30pm then rapid clearing, breezy, cooler temps, 1.69" rain today, things are green again! 10: Partly cloudy, pleasant temps & humidity, light W breezes, very nice day. 11: Cooler overnight low 55, partly to mostly sunny, low humidity, very light winds. 12: A clear cool night and morning with a low of 48, then warm & sunny with low humidity and light NW breezes. 13: Fair early then increasing clouds, warm, more humid, light winds. 14: A period of heavy rain and thunder commencing around daybreak and mostly ending by 8:30am. Some fog, mostly cloudy, brief downpour about 7:30pm, total rain today .97". 15: Cloudy and cool, several brief afternoon t-showers, only .25" here but a lot more rain fell in some other parts of town. High only 68. 16: Mostly cloudy early then gradually decreasing clouds and humidity, light-moderate N winds. 17: Fair & cooler overnight, then mostly sunny and very warm, light W winds, low humidity. Some faint "heat" lightning from storms well to our SE late this evening, no thunder. 18: Partly cloudy, very warm, light W winds. 19: A relatively cool night then a partly cloudy hot day with increasing humidity. Thunderstorm formed overhead this evening about 6:15pm and brought a brief cooling downpour .22", rain became very heavy on the east side of town where hail and high winds were also observed. 20: Early fog then mostly sunny & warm, light WSW breezes. 21: Variably cloudy, warm and humid. Weakening line of storms passed through around 5:30pm with more showers this evening 9-11pm .42" rain fell. 22: Partial clearing overnight, becoming mostly sunny during the afternoon but temperatures only reaching the 70s before quickly dropping again making for a cool evening. *RARE 5.8 EARTHQUAKE* 23: Cool low 46 F overnight with clear skies, then a beautiful sunny warm day with low humidity. While the weather was quiet, a very rare, fairly intense (5.8) earthquake hit central VA at 1:51pm rattling the entire eastern US, our house shook notably 10-15 seconds but no damage. 24: Cool AM with increasing clouds, partly to mostly cloudy, warm, humid, moderate SSW breezes. 25: A series of strong thunderstorms this morning from about 5-8am. Frequent lightning, several brief downpours, and strong SW wind gusts 30-40 mph .99" of rain fell, fog briefly formed. Variably cloudy, breezy, brief shower @ 4:30pm brought day's total rain to 1.07". 26: Clearing and cooler overnight low 56. Sunny AM, partly sunny PM, warm high 83, little wind. 27: Partly to mostly cloudy with a couple brief showers late this evening around 9:30pm from the western edge of Hurricane Irene, which is currently battering eastern PA and the east coast. 28: Cloudy and becoming windy overnight as Irene passed east of the area. Mostly cloudy, cool, breezy with NW winds gradually diminishing. Few mid-afternoon sprinkles, then clearing. 29: Clear & cool overnight low 49 F. Partly sunny AM, mostly sunny PM, cool and quiet. 30: Clear & cool overnight low 46, 100% sun, warm afternoon, little wind, low humidity. 31: Mostly clear overnight, partly cloudy all day, warm, light SW winds. MONTHLY SUMMARY August won't soon be forgotten by many from North Carolina to New England. Extremely heavy rains deluged the state east of the Susquehanna River, with over 20 inches of rain in the Philadelphia area and parts of New Jersey. Clusters of slow-moving thunderstorms dumped tremendous amounts of rain multiple times during the month, and Hurricane Irene dumped an additional 6-12" of rain on many of the same areas. The result was severe flooding and record rainfall totals rivaling those of August 1955, when Hurricanes Connie and Diane dumped up to 2 feet of rain in a week on some areas. Mother Nature had already shaken things up, literally, as a rare, strong and unusually far-reaching earthquake rattled nearly the entire eastern US on the 23rd. I personally felt the 5.8 quake for about 10-15 seconds, a very rare event. The earthquake caused scattered damage but no injuries, and was quickly an afterthought, as the focus shifted to Irene, which battered the entire east coast. Her local effects were very mild, with little rain and 30-40 mph wind gusts. Despite missing most of the moisture from Irene, precipitation was well above normal, thanks to several heavy thunderstorms that rumbled through the area. Nearly all of August's 6.90" of rain was attributed to hit-and-miss thunderstorms, and over 5" of this total fell in the first half of the month, nearly as much as what fell in all of June and July combined. The heavy rains early in the month quelled the developing drought conditions, and all of the parched lawns in the area bounced back to life. By month's end, everything was lush and green again. Temperatures were slightly above normal, our 5th consecutive month with above-average temps. August began hot, with 3 of the first 4 days in the 90s, before the soaking rains came. Low temperatures were on the mild side, in the mid-upper 60s, the first 10 days, but, unlike the typical trend of above normal mins contributing to the positive temperature anomaly, lows often reached the 50s, with a handful of nights reaching the 40s. Min temperatures were below average but max temperatures were above, with primarily seasonal 70s and 80s, but skewed upward by a few readings in the low 90s. Plenty of sun between storm events also helped temperatures rebound quickly - even when lows reached the 40s, the highs usually rebounded well into the 80s. While statistically August was somewhat warm, it felt refreshingly cool after a scorching hot July.