MONTHLY WEATHER DATA AND OBS - WESTMONT 1.1W PA MAY 2013 OBSERVERS NATE & STEVE 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 71 48 54 2 73 44 54 3 68 46 52 4 66 41 52 5 71 44 50 6 65 42 54 T 7 64 53 55 .11 8 71 50 51 .56 T 9 72 49 55 .36 10 73 52 57 .50 T,DW 11 59 50 50 .45 12 51 36 40 .05 13 50 33 36 T T S 14 55 27 48 Frost/freeze 15 83 45 72 .02 T 16 77 59 62 .33 T 17 81 54 62 F 18 76 52 58 19 64 55 61 20 79 60 67 .03 21 87 61 72 22 86 63 63 .05 T 23 76 57 57 .25 T 24 57 38 38 .06 25 60 35 45 26 67 37 49 27 62 37 51 .03 28 71 49 62 .82 F,T 29 83 59 66 30 87 58 69 F 31 89 60 68 AVG/SUM 70.8 48.2 55.8 3.62 T - EXT 89 27 72/36 0.82 T - Date 31 14 21*/13 28 13 - *=Also occurred on earlier dates Miscellaneous Stats Mean Monthly Temperature: 59.5°F (+0.8°F) Year precipitation to date: 17.08" (-2.14") May precipitation departure: -0.69" Season snowfall to date: 108.9" Number of days with: Fog 3 Sleet 1 Thunder 7 Damaging Winds 1 DETAILED OBSERVATION NOTES SUNNY - DRY - PLEASANT 1: Mostly sunny with pleasant temps and light south winds. 2: Sunny and pleasant again with light west winds. 3: Sunny and pleasant with light SW winds, occasionally breezy. 4: Mostly sunny and breezy, slightly cooler. 5: Mostly sunny and pleasant. Very dry with a min relative humidity of 19%! 6: Clear & cool overnight. Increasing mid-afternoon clouds with a few spits of drizzle. UNSETTLED 7: Overcast with occasional light rain and drizzle, mainly in the evening, with heavy rain just south of us all day. 8: A period of predawn rain with an additional .31" falling by 7 am. Mostly cloudy with occasional brief showers during the day and a thunderstorm around 5pm that moved in from the northeast. More storms formed in that direction headed our way but stalled then dissipated just NE of town. An automated rain gauge at Mineral Pt. recorded 1.77" of rain. 9: Mostly cloudy with occasional brief showers and a couple of brief heavy downpours again around 5pm .36" of rain fell mostly in about 10 minutes. Winds were gusty at times and slowly shifted from N to NW then W. SQUALL LINE WIND DAMAGE 10: Mostly cloudy with near calm winds. A rain shower from about 10:45am-noon. Mild & humid afternoon with a brief but intense thunderstorm from a squall line that whipped through about 6:30pm with very strong winds 50+ mph and a brief burst of rain. Several small branches blew down in the yard with scattered tree and wire damage in and around town. More showers late this evening 10pm-midnight with a total of .50" rain falling today. 11: More rain showers on and off overnight and through much of the day with persistent light drizzle, another .45" fell. Temperatures steady in the 50s all day with breezy conditions at times. LATE SEASON CHILL 12: A couple of brief overnight showers. Partly cloudy, breezy and blustery with a high of only 51. Chilly evening. 13: Chilly overnight low 33 F with breezy & blustery conditions continuing. Temperatures were in the 30s all morning and late-season snow flurries and a few ice pellets fell. Variable clouds - high just barely reached 50 this afternoon. 14: Clear and very cold overnight low 27 F with a hard frost. Another cool day high 55 F though with less wind. FROM WINTER TO SUMMER 15: Cool overnight low 45 F though nothing like last night. Partly cloudy, very warm and somewhat humid. High was 83, a spectacular rebound after a low of 27 just yesterday morning! Some late evening thunder with a couple brief showers. 16: Rain early this morning with some imbedded thunder. Partly cloudy and warm high 77 F, became clear this evening. 17: Patchy fog this morning, then partly cloudy, very warm again high 81 F though dry with minimum humidity in the 30s. 18: Variable clouds with temperatures dropping rapidly from mid-afternoon on. Light-moderate SSE in the evening. 19: Cloudy all day with steady temperatures and light SW winds. 20: Partly cloudy and pleasant with mostly calm winds, occasional gusts from the S. Brief rain shower around 3:15pm. VERY WARM - SCATTERED SHOWERS/STORMS 21: Mostly sunny, very warm high 87 F, light SW winds. Very summer-like day. 22: Variable clouds and again very warm high 86 F and quite humid. A solid line of strong to severe thunderstorms split right as it moved in around 5pm. Gusty SW winds but little rain only .05" fell. Storms were heavy just NE of town. 23: Mild overnight with a few showers early to mid-morning. Warm, very humid, again variably cloudy. This afternoon and evening was a carbon copy of yesterday, as a solid line of strong to severe storms once again split and went around this station in virtually every direction. Only .12" rain and modest wind gusts. Total rain today .25". ANOTHER COLD SNAP 24: A few overnight showers and early morning drizzle, then mostly cloudy, breezy & blustery with rather chilly temps. Today's high of 57 was set at midnight - the daytime high was a mere 46...this coming barely a week from June! 25: Chilly overnight low 35 F, no frost. Partly to mostly sunny skies, breezy and cool with a high of 60 F. 26: Sunny, chilly overnight and continued breezy. Slightly milder high 67 F, cool evening again with a few high clouds. 27: Sunny through most of the morning and again cool but no frost. Became overcast during the PM hours with a steady but very light rain from about 5-8pm, only .03" fell in 3 hours. High of only 62. Winds were very light & variable. SOME DECENT RAIN - VERY WARM 28: A couple of predawn showers with briefly heavy rain, .24" fell. Frequent rain showers, heavy at times, from about 6:30-11:30am with some light patchy fog. Mild and very humid afternoon with a brief thundershower ~ 3:45pm. Winds were light SW with some mild gusts (~20mph) around the storm. A total of .82" rain fell today and was much needed. 29: Mostly cloudy overnight with rising temps early this morning. Strong SW breezes, mostly sunny and warm high 83 F. 30: Valley fog early this morning, otherwise mostly sunny with near calm winds and very warm high 87 F. 31: Mostly sunny and hot high 89 F with calm to light SW winds. MONTHLY SUMMARY May 2013 took us on a rollercoaster temperature ride. The month began with tranquil weather, steady temperatures the first week. However, the 2nd week was wild. Showers and thunderstorms fell every day from the 7th-12th. The most intense thunderstorm was on the 10th, when a downburst hit the area with severe winds, causing scattered tree and power line damage. Temperatures plunged behind this cold front. Late season snow flakes and ice pellets flew on the 13th, followed by a hard freeze and frost (27F) the 14th. The high on the 15th? A summer-like 83. From the 15th-23rd, temperatures were well above normal. Another late season chill with some local frost (none at this station) invaded the area the 24th-27th, with temperatures in the 30s each night. Again, unseasonably cold air, opposite the recent trend of hot memorial day weekends, abruptly rebounded at the end of the month to a hot 89 on the 31st. Despite the yo-yo pattern and a few chilly readings, temperatures were slightly above average in May. For the 4th time in the first 5 months of 2013, precipitation fell below average in May. The trend of many days with precipitation but little of any consequence continued. The only day in 2013 with over inch, and barely, was Jan. 30 when 1.01" fell. On several occasions, thunderstorms and heavy rain narrowly missed this station, most notably just to the northeast. Storms dropped nearly 2" in that direction on the 8th, with only .56" here. Thunderstorms dropped nearly 2" total on the 22nd-23rd, while only .30" fell here. The month's heaviest rain (0.82" the 28th) was quickly followed by the summer surge at the end of the month after a warm front passed through. Though there were 7 days with thunder, most of the storms - with the notable exception of the 10th - were locally quite mild.