681 
fxus62 kmhx 140155 
afdmhx 


Area forecast discussion 
National Weather Service Newport/Morehead City NC 
855 PM EST Sat Mar 13 2010 


Synopsis... 
an upper level area of low pressure will linger near the middle 
Atlantic coast into Monday. A broad area of high pressure will 
build toward the area from the north and west early next week. A 
weak surface low will develop of the southeast coast Wednesday and 
linger into Friday. 


&& 


Near term /through tonight/... 
as of 810 PM Sat...upper low continues to approach the area from the 
west tonight. RUC places it in vicinity of County Warning Area near sunrise. 
Southwest flow at the surface will continue over the area through 
the night as surface low meanders around in Virginia. Isolated 
showers to the west. Drier air moving into County Warning Area so am not real 
impressed with precipitation chances. Will keep probability of precipitation 20 or below for 
tonight. Wouldnt be surprised an an instability shower or two as 
upper low moves across area...but that is not expected until after 
sunrise. Temperatures in the 50s this evening on their way to the 
middle 40s later tonight. 


Previous disc...as of 245 PM Sat...surface low is currently located in 
central Virginia...while upper low continues to dive southeast into the Tennessee 
Valley. Turned out to be a pleasant day across eastern NC. Few 
showers now trying to develop to the west of the coastal plain. 
Could see some isolated showers and thunderstorms this 
afternoon...mainly in the coastal plain and the northern 
counties...with coverage increasing slightly tonight. But have 
capped it at chance for the northern tier...mainly north of Highway 264. 
Think coverage will be limited given the drier air working its way 
into the area...with dewpoints currently in the upper 40s and 
continuing to drop. But if thunderstorms were to develop...there is 
potential to see isolated strong storms given steep lapse rates and 
cold temperatures aloft...wouldn't take much to see hail with low freezing 
levels and wbz heights. Instability should decrease significantly 
after 06z. Clouds will continue to increase from the SW as upper low 
approaches the area. Overnight lows in the middle/upper 40s. 


&& 


Short term /Sunday through Monday night/... 
as of 245 PM Sat...challenging forecast continues with upper low 
lingering and energy rotating around it. NAM/GFS in good agreement 
with track of upper low. Low will be directly over NC Sunday 
morning and then move NE off the middle-Atlantic coast Sunday 
evening. Slight chance showers possible throughout the day Sunday 
into Monday evening...through difficult to pin down with middle level 
energy rotating around the upper low. Temperatures in the low 60s/upper 
50s through the period under partly-mostly cloudy skies. 


&& 


Long term /Tuesday through Saturday/... 
as of 245 PM Sat...relatively quiet extended period as high 
pressure builds in from the west. Weak low pressure will develop 
off the southeast coast Wednesday and linger into Friday. High pressure 
will build over the area Saturday ahead of next frontal system. 
Temperatures slightly cooler than normal through the period under north/NE 
flow...warming by early weekend with highs around 70 degrees. 


&& 


Aviation /01z Sunday through Thursday/... 
as of 840 PM Sat...VFR expected overnight. Areas of ac/SC will 
rotate across area overnight as upper low gradually moves east. More 
widespread scu expected Sun morning with axis of upper low moves in. Some 
MVFR ceilings/visibilities possible with rain showers activity but appears most activity 
will remain north of taf sites. 


Surface low to the north will gradually slide offshore Sunday then move southeast 
offshore of the CST Monday into Tuesday. Will see mainly wrly winds 
through late Sun night with VFR expected. By Monday night into Tuesday 
winds become more north/NE and with developing inversion will see some 
lower ceilings...poss in MVFR range. Mainly VFR Wednesday and Thursday as init 
low departs with weak high building in. Another low expected to 
develop offshore Thursday and may have enough moisture to lower ceilings 
near CST. 


&& 


Marine... 
as of 840 PM Sat...no changes with evening update. SW winds have 
increased over area this evening and forecast on track. Small Craft Advisory marginal for 
Pamlico Sound but period of 25 knots gusts expected into overnight. 
Latest buoy observation show seas 5-8 feet off Duck and 10 feet at 41025...forecast 
on track. 


Will continue high surf advry for the obx area as still have large southeast 
swells. 




&& 


Mhx watches/warnings/advisories... 
NC...high surf advisory until 1 am EST Sunday for ncz103-104. 
Marine...Small Craft Advisory until 4 am EDT Sunday for amz135. 
Small Craft Advisory until 6 PM EDT Thursday for amz150-152- 
154. 
Small Craft Advisory until 6 am EDT Monday for amz156-158. 


&& 


$$ 
Synopsis...cqd 
near term...cgg 
short term...cqd 
long term...cqd 
aviation...jbm/rf 
marine...jbm