549 
fxus62 kmhx 151954 
afdmhx 


Area forecast discussion 
National Weather Service Newport/Morehead City NC 
354 PM EDT Monday Mar 15 2010 


Synopsis... 
an upper level low will slowly push southeast off the middle Atlantic 
coast tonight...then move rapidly east Tuesday. High pressure 
will build in from west late Tuesday through Wednesday. Weak low 
pressure will develop off the southeast coast Wednesday through 
Friday. High pressure will build back over the area Friday through 
Saturday ahead of next frontal system. 


&& 


Near term /until 6 am Tuesday morning/... 
vertically stacked low pressure will continue to slowly migrate southeast off 
the middle Atlantic coast overnight. Lift associated with a vorticity maximum 
rotating around the low is bringing light to moderate showers from 
the northern obx to central Virginia this afternoon. The showers will 
continue to transition southeastward into the region this evening and will 
continue likely probability of precipitation across the NE portion of the County Warning Area tapering to 
slight chance SW. Quantitative precipitation forecast amounts will be light with generally less 
than a tenth inch expected at the most. Showers are expected to 
diminish late this evening and overnight as best forcing moves 
offshore. Cold air advection continues overnight with moderate north/northwesterly flow but 
clouds and good mixing will keep min temperatures in the l/m40s. 


&& 


Short term /6 am Tuesday morning through Tuesday night/... 
the low pressure off the coast will quickly slide eastward through the 
short term as surface high pressure builds in from the west and a broad middle 
level trough moves into a majority of the eastern half of the Continental U.S.. 
continued northerly flow will bring cold air advection and abundant moisture in the 
form of clouds across the region. Limited sunshine will keep temperatures 
well below seasonal norms and highs only expected in the l/m50s 
inland but northerly flow across cool Labrador current will only see 
m40s across obx. Moisture/clouds diminish late Tuesday night and winds 
expected to decouple allowing for better radiational cooling. Lows 
expected in the m30s inland to l40s coast. 


&& 


Long term /Wednesday through Monday/... 
a weak shortwave moves across the southeast Wednesday with low pressure developing 
off the southeast coast. Models continue to track the low well offshore 
but are not in best agreement with how much precipitation will reach the 
Carolina coast. Will keep slight chance probability of precipitation for only immediate 
coast from Hatteras south Wednesday night and Thursday. Shortwave ridging 
aloft and surface high pressure will fair conditions and continued airmass 
moderation across the region Thursday night through Sat. A longwave 
upper trough slides into the central Continental U.S. Sat and moves toward 
the region late in the weekend. Strengthening southerly flow ahead of a 
frontal system will bring increasing moisture across the region 
although best lift will occur ahead of a cold front currently 
prognosticated to cross the region Sun night. Temperatures expected to be a few 
degrees below normal Wednesday then at or above normal through the rest 
of the long term. 


&& 


Aviation /19z Monday through Saturday/... 
as of 230 PM Monday...expect mainly broken ceilings around 5000 feet through the 
evening. As north winds develop later tonight will see an inversion 
form with plenty of moisture trapped below it. Expect MVFR ceilings 
from late tonight through most of Tuesday. Forecast soundings show clouds 
lifting and scattered out later Tuesday night with mainly VFR expected rest of 
forecast period. 


&& 


Marine... 
as of 230 PM Monday...low pressure to the NE will drop southeast well offshore of 
the coast tonight and Tuesday. Models show gradient tightening and northwest to north 
winds increasing overnight. Onset of stronger winds looks to be 
delayed a bit so adjusted start time of Small Craft Advisory until later this evening 
sounds and southern waters. Winds will maximum out early Tuesday off hat with 25 
to 30 kts expected. These winds will build seas to 7 to 10 feet over 
the northern and central waters Tuesday and have issued a high surf advry for 
mainly the northern obx late tonight through Tuesday night. Winds will diminish 
Wednesday as high pressure builds across however seas will continue in Small Craft Advisory range north 
of Ocracoke. Weak low expected to develop offshore Thursday however at 
this point looks to be far enough offshore and weak not to increase 
winds much. Seas shld finally drop below Small Craft Advisory levels central and northern waters 
Thursday night. High pressure will build in from the west Sat with light winds 
and seas. 


&& 


Mhx watches/warnings/advisories... 
NC...high surf advisory from 2 am Tuesday to 6 am EDT Wednesday for 
ncz103. 
Marine...Small Craft Advisory from 9 PM this evening to 7 PM EDT 
Tuesday for amz130-135-158. 
Small Craft Advisory until 3 am EDT Friday for amz150-152-154. 
Small Craft Advisory from 9 PM this evening to 2 am EDT 
Wednesday for amz156. 


&& 


$$ 
Synopsis...sk 
near term...sk 
short term...sk 
long term...sk 
aviation...rf 
marine...rf