MONTHLY WEATHER DATA AND OBS - LAVALE MD APRIL 2010 OBSERVER SCOTT LOHR DATA COMPILED AND PUBLISHED BY NATE MULLINS Special Observations: F=fog, T=thunder, H=hail, S=sleet, G=glaze, DW=damaging winds Observation time for this station is midnight. Temperature, °F Precipitation, In. Liquid Solid 7am DAY 24-hour Rain Snow/ Snow Special WEATHER Date Max Min Equiv Ice Depth Obs. SUMMARY 1 82 40 Mostly sunny, warm 2 86 48 Sunshine, very warm with SE breezes 3 84 53 Partly cloudy, continued very warm 4 76 54 Partly sunny, warm 5 78 43 .01 Partly cloudy, brief shower 6 92 59 Sunny, RECORD HEAT, low humidity, strong S winds 7 92 69 Partly sunny, RECORD HEAT AGAIN, breezy 8 82 45 .11 Partly cloudy and warm again, PM shower, falling temps late 9 45 43 T Mostly cloudy, much cooler, sprinkles 10 65 38 Partly cloudy, breezy 11 73 38 Mostly sunny 12 72 42 Partly sunny 13 49 47 .09 Cloudy, AM light rain showers, much cooler 14 62 37 F Cool with AM fog, then sunny & milder 15 78 38 Fair and warm 16 80 51 .25 T Partly cloudy, warm, windy, evening showers (distant thunder) 17 56 39 Partly cloudy, strong NW breezes, much cooler 18 49 38 Partly cloudy, cool and breezy 19 64 38 Sunny & milder 20 64 35 Fair to partly sunny - high clouds 21 68 43 Partly sunny 22 66 38 T Partly cloudy, breezy, sprinkes 23 71 43 Partly cloudy, breezy 24 61 48 .05 Mostly cloudy, occasional light rain 25 72 50 .53 F,T Mostly cloudy, humid, PM heavy rain shower with thunder 26 60 52 .25 F Mostly cloudy, showery 27 53 47 Partly cloudy, breezy 28 53 38 Partly cloudy, windy 29 68 34 Mostly sunny, mild after cool AM (frost), breezy N Winds 30 83 43 Mostly sunny and very warm with light NW winds AVG/SUM 69.5 44.4 1.29 0.0 - EXT 92 34 0.53 - - Date 7* 29 25 - - *=Also occurred on earlier dates Miscellaneous Stats Mean Monthly Temperature: 56.9 F (+5.1 F) Year precipitation to date: 12.06" (-1.04") Monthly Precipitation Departure: 1.29" vs. 3.68" (-2.39") Season snowfall to date: 78.3" Number of days with: Fog 3 Thunder 2 NOTES/SIGNIFICANT EVENTS 1: Very warm high 82 F just misses the record high of 83 in 1986. Big rebound from a low of 40. 2: RECORD HIGH 86 F edges old record of 85 in 1963. 3: Very warm again high 84 F is 2 degrees shy of the record 86 set in 1981. 6: RECORD HIGH 92 F shatters the daily record of 84 in 2005 and also is a new all-time record for the EARLIEST EVER 90-degree day. The old record was April 17th, 2002 (90 F). Also, the low of 59 F shatters the record high min temperature of 50 set way back in 1967. Wow!!! 7: ANOTHER RECORD HIGH 92 F shatters the old record of 83 in 1954. A balmy low of 69 F this morning also demolishes 1967's mark of 54 F for a record low min temperature and is also only 1 degree shy of the all-time record warmest min for April, 70, set on April 26, 1990. This is the warmest first week of April ever with a mean temp of 68.3 F. Nothing has ever come close to this kind of record early season heat! 8: Near-record high 82 F (record was 85 in 1991). The low of 56 would have been a record, but a sharp cold front dropped temperatures to 45 by midnight (obs time). A shower this afternoon dropped .11" with severe storms missing our area, especially to the north & east. 9: Dramatically cooler with a high of only 45 F and a few sprinkles 13: Another cool day with a high of 49 F and light rain. 16: Warm high 80 F. Severe storms weakened as they crossed the mountains during the evening. Evening rain showers dropped .25" with wind gusts to 30 mph. Areas to our north in PA had severe storms and damaging winds. 18: Cool high only 49 F and breezy, a bit blustery. 24-26: 0.83" of much-needed rainfall. Heavy rain and thunder late on the 25th. 29: Monthly low of 34 F with frost. Milder this afternoon with a high of 68 and sunshine. 30: Very warm again high 83 F. MONTHLY SUMMARY April 2010 will be remembered for its unusually warm temperatures and record heat during the 1st week of the month, which was actually the warmest week - and while temperatures were above normal much of the month, the temperature trend was somewhat backwards, with some of the coolest readings near the end and the warmest early in the month. Five daily high temperature records (3 record highs, 2 of which coincided with record high mins) were set within the first week. 86 F on the 2nd was the warmest temperature yet for a year (85 was the previous record and was recorded also multiple times in March), and the 92 readings on the 6th and 7th were unparalleled in recent his- tory, marking the earliest 90+ degree readings ever. The previous record was April 17th, 2002, with a high of 90. The min of 69 on the 7th was the warmest ever for so early in the season, and was within 1 degree of the all-time warmest April min of 70 on April 26, 1990. Temperatures were well above normal in both the max and min temperature department, about equally, with the mean max of 69.5 and mean min of 44.4 both ranking 3rd warmest, and likewise, the month's overall mean temperature of 56.9 F was 3rd warmest. Had it not been for a few unseasonably cool readings in the 40s, all of which followed frontal passages (and skewed the mean downwards quite a bit), this would have likely been the warmest April on record. 56.9 F is only 0.1 degree F shy of the record of 57.0 set in Aprils of 1954 and 1994 (1954 was technically the warmest, by expanding the digits). Another noteworthy stat was that temperatures never reached freezing, for the first time ever in April. The low was 34, 10 degrees above the "average" extreme low of 24 for the month. April ranked as the 18th warmest month (standard deviations above normal) since records began in 1948. Needless to say, April was a month for the record books. The very warm pattern continued March's major temperature reversal, as this near-record warm April followed the 4th warmest March on record. These two unusually warm months immediately followed one of the top 10 coldest winters and the snowiest winter season on record. April 2010 also entered the record books for its lack of precipitation. We were looking at record dryness, with a meager .46" of rain falling through the 23rd, before a slow-moving system, mostly passing north of us, dropped .83" of rain, most of it on the 25th-26th. This accounted for about 2/3 of the month's precipitation and saved us from record dryness. Still, this was the 3rd driest April since records began in 1948, with a mere 1.29" of precipitation. The lack of rainfall (and no measurable snowfall, not even a trace) can be attributed to the dry airmasses, with a relatively zonal flow and very short-lived troughing and ridging. While there were about an average number of frontal passages, these fronts were moisture-starved, tapping little Gulf or Atlantic moisture, our main sources for heavy precipitation. The most notable frontal passages were on the 8th (which was associated by scattered severe thunderstorms, all of which missed this location), 16th (another day with a signficant severe weather outbreak, but most of the severe storms were to the north or east) and 26th. These led to several short-lived cool spells, but between frontal passages, temperatures were in the record to near-record warm category. April was also a relatively windy month, but with no damaging winds in the local area. Some areas just to our north in PA had 60 to 80 mph winds from an intense squall line that raced across the state on the afternoon and evening of the 16th. Locally, there was no severe weather, and only two days had thunder and three had fog, and only a scattering of frost with an unusual lack of cold weather. In summary, April 2010 was quiet, very dry and exceptionally warm. Additional notes/records: 1: High 82 just misses record of 83 in 1986. 2: RECORD HIGH 86 F breaking old record of 85 in 1963. 3: High 84 F, 2 F shy of record 86 in 1981. 6: RECORD HIGH 92 F shatters 2005's record of 84 and is the earliest EVER 90-degree day. Record high min temperature of 59 F was also set. 7: RECORD HIGH 92 F shatters the 1954 record of 83, and the min of 69 is a record high that shatters the previous 1967 record 54 F and is 1 F shy of the all-time April record of 70. April 2010 ranked 3rd warmest on record with a mean temperature of 56.9 F, only 0.1 F shy of the warmest April ever on record 57.0 F set in 1954 & 1994. The average max of 69.5 F ties for 3rd warmest with April 1981, and the mean min of 44.4 F also ranks 3rd warmest. The high- est April mean min record was set just two years ago in 2008 (45.7 F). This comes on the heels of the 4th warmest March since records began in 1948 and continues the big temperature reversal from the persistent cold and record snowy winter of 2009-2010. April 2010 also ranked 3rd driest April on record with only 1.29" of precipitation all month. The driest April on record is 0.84" in 1971 and the 2nd driest is 1.01" in 1997. Despite a very warm and nearly snowless early spring, the 2009-2010 cold season snowfall (barring any measurable snow in May, which has never happened - a trace has fallen in 2 of 62 years) total to date is 78.3", which will still rank as the 3rd snowiest cold season snow/ice tally on record.