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NWS Discussion
			
				

Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia 
936 am EDT Wednesday Jun 19 2013 


Synopsis... 
high pressure over Lake Huron will build into the northeastern 
U.S. Through Friday. The high will move offshore this weekend 
into early next week...bringing a return of warm and humid 
conditions. 


&& 


Near term /until 6 PM this evening/... 
reinforcing front will push south into southern Virginia today. 
Much of the County Warning Area already has north winds...although some clouds 
still linger north of the boundary. These clouds will gradually 
press southward through the day as well...with mostly cloudy skies 
becoming partly sunny and perhaps even mostly sunny across the 
northern portion of the County Warning Area. 


Much of the County Warning Area should also be dry...with drier and more stable 
air pushing south. There may be just enough moisture across the 
south/southwest County Warning Area closer to the boundary as well to pop isolated 
diurnal convection as supported by recent runs of the WRF-arw. 


Any diurnally-driven convection would dissipate early this 
evening...with clearing skies overnight and cooler temperatures. 


&& 


Short term /6 PM this evening through Thursday night/... 
and the final moments of Spring look to end on a fine note in the 
middle Atlantic as well... high pressure over the northestern U.S. Tonight through Thursday night. 
Dewpoints continue on the dry side. Lows in the 50s both ngts west of 
I-95...60s in the cities and along the Bay. High temperatures Thursday in the 
l80s. 


&& 


Long term /Friday through Tuesday/... 
broad upper ridge over the central Continental U.S. Builds eastward into the 
Middle-Atlantic States on Friday and remains overhead this weekend into 
early next week. At the surface...region will be situated on western periphery 
of an Atlantic high. Temperatures will trend slightly warmer each day 
under the influence of weak return flow but oppressive heat not 
expected to develop with this pattern. 


Most of the area will be rain free through the weekend with subsidence 
inversion capping convection. However...isolated pop up showers and 
storms are possible over the mts during the peak heating hours each 
day. 


Slightly higher chances for afternoon showers and storms early next week as 
subsidence inversion weakens and boundary-layer moisture increases. 
For right now...have confined chance probability of precipitation to the higher terrain 
without organized forcing to maintain convection too far east of the 
mts. 


&& 


Aviation /13z Wednesday through Sunday/... 
reinforcing cold front has already pushed south of The Hubs...with 
northerly winds in place. Still have some clouds however. Scattered-broken 
MVFR may linger through middle morning...but VFR will prevail during 
the afternoon. 


Mainly VFR through early next week. Patchy radiational fog may reduce 
visibilities during the early morning...especially during the fog prone 
terminals such as mrb/cho. 


&& 


Marine... 
north/NE winds were gusting at or above 20 knots through the middle portion of the 
Bay and have expanded Small Craft Advisory. Winds should diminish later in the 
afternoon. 


High pressure over the Great Lakes will track east towards New England tda/tngt. 
Although the pressure gradient is not great...suspect that the warm/channeling 
down the ches Bay could bring gusts to Small Craft Advisory levels...with the waters 
S of drum pt being the most likely location. An Small Craft Advisory has been issued 
there for the afternoon hours. 


No probs expeceted on the waters tonight through Thursday night. 


Light southerly winds through the weekend with hipres in control. 


&& 


Lwx watches/warnings/advisories... 
District of Columbia...none. 
Maryland...none. 
Virginia...none. 
WV...none. 
Marine...Small Craft Advisory until 6 PM EDT this evening for 
anz531>534-538-543. 


&& 


$$ 
Bpp/Woody!/Jrk