MONTHLY WEATHER DATA AND OBS - LAVALE MD							
MAY 2013							
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	70	54					Fair/sunny
2	73	41
3	68	45
4	69	42
5	68	42
6	57	43	 .14				Late PM rain
7	60	54	1.54			F	Record rainfall (old record 1.36" in 1999)
8	68	50	 .50			F	Overnight rain
9	71	49
10	80	53	 .39			T,DW	PM severe thunderstorm with scattered wind damage
11	70	58	 .25				Rain showers
12	56	47
13	49	34					Record low max 49 F (old record 53 in 1996)
14	59	33					Scattered frost
15	89	46					Dramatic warm-up
16	77	62	 .15			T	Mild early AM showers with thunder
17	82	50
18	59	56
19	66	57
20	85	61				T	PM thunder, no rain
21	88	63				F	Dense AM fog
22	86	59	 .11				Warm, humid, severe storms east of station
23	77	60	 .03
24	66	41	   T				Much cooler
25	61	40
26	64	39
27	62	40
28	76	53	 .02
29	87	60					Very warm
30	90	58					"
31	89	62					"

AVG/SUM	71.7	50.1	3.13	0.0	-
EXT	90	33	1.54	-	-
Date	30	14	7	-	-
*=Also occurred on earlier dates
							
Miscellaneous Stats
			
Mean Monthly Temperature: 60.9°F (+0.1°F)						
Year precipitation to date: 12.42" (-4.93")	
May precipitation departure: -1.06"					
Season snowfall to date: 47.9" (+7.4")						
Number of days with: 
Fog 3
Thunder 3 
Damaging Winds 1	

Note: The high of 49 on the 13th not only set a record low, but was the latest date of highs in the 40s
in 65 years of records.	

MONTHLY SUMMARY	

May brought near normal temperatures, despite some dramatic temperature swings. Temperature were almost
exactly average, just 0.1°F above. Slightly below normal max temperatures offset slightly above normal min
temperatures. Following a cold front on the 11th, unseasonably cold readings near freezing occurred the
13th and 14th, with scattered frost. However, the month's low of 33 on the 14th was immediately followed
by a dramatic temperature rise to 89 on the 15th, one degree F shy of the month's high of 90 on the 30th.
The final week brought unseasonably cool temperatures, again followed by very warm readings at the end of May. In stark constrast to almost every year since 2005, Memorial Day Weekend was cool and dry. In most
years from 2006 to 2012, Memorial Day weekend had record or near-record heat and scattered strong to
severe thunderstorms.

May's precipitation pattern followed suit of all previous months in 2013, in that it was below normal,
though not excessively so. The vast majority of the month's rain fell in a six-day period from the 6th to
11th. A cut-off low pressure over the southern Appalachians drifted northeastward into the Mid-Atlantic on
the 7th and 8th. An easterly wind flow on the north side of the system brought ample amounts of moisture
from the Atlantic Ocean, with local rainfall totals averaging in the 1.5 to 2.5 inch range. Shortly
thereafter, the month's most severe thunderstorm brought a brief period of intense rain and wind on the
afternoon of the 10th. Showers continued on the 11th, prior to the aforementioned cold frontal passage.
The balance of the month was quite dry, with only a few glancing blows from scattered showers and storms.