247 
fxus61 kmhx 200841 
afdmhx 


Area forecast discussion 
National Weather Service Newport/Morehead City NC 
435 am EDT Sat Mar 20 2010 


Synopsis... 
high pressure extending over the area from the south will gradually 
move offshore tonight and Sunday. Strong low pressure will approach 
from the southwest Sunday night...then move across north of the area 
Monday and Tuesday. High pressure will build in for middle week. 


&& 


Near term /until 6 PM this evening/... 
weak high pressure extending over area will produce fair and warm 
conditions for first day of Spring. Dry atmos...good insolation and 
slightly higher low level thicknesses will support maximum temperatures 3-5 degrees 
warmer inland than on Friday...while sea breeze off cool water will 
limit warmer temperatures for coast. 


&& 


Short term /6 PM this evening through Monday night/... 
fair and dry conditions will continue tonight and Sunday with high 
pressure gradually moving offshore. More cloud cover and decreasing 
thicknesses will keep maximum temperatures a few degrees cooler Sun afternoon. Upper 
low with attendant surface system will bring in next chance of 
precipitation...mainly late Sun night through Monday afternoon. Kept probability of precipitation in chance 
range for Sun night with likely for Monday. Instability will be 
marginal and kept wording as showers likely with chance thunderstorms. Some 
stronger wind gusts possible but severe threat appears very isolated. Slight chance 
probability of precipitation for Monday night for possible activity with upper low moving across. 
MOS blend reasonable for temperatures through period. 


&& 


Long term /Tuesday through Friday/... 
upper low will continue slight chance probability of precipitation Tuesday. Dry for Wednesday and Thursday then 
next system approaches Friday and added chance probability of precipitation during the day. 00z 
models indicate weak secondary front moving through Wednesday night but no 
precipitation with it. 


&& 


Aviation /08z Saturday through Wednesday/... 
as of 245 am Sat...main question this taf is potential shallow fog 
formation under clear skies/light winds. Agreed with previous taf 
that atmosphere is a bit too dry to support widespread fog so kept 
out...but not ruling out a couple hours of occn MVFR visibilities towards 
daybreak as temperatures cool closer to dewpoints. Otherwise expecting 
VFR today with sky as deep layered ridging gradually shifts 
offshore. 


Expect VFR conditions to prevail through Sunday. Some low potential 
for minor ground fog again early Sunday morning with a bit more moisture 
in developing return flow pattern...but this threat appears to be 
minimal at this point. Model time sections suggest high cloudiness 
will increase on sun then gradually lower into sun evening in 
advance of next frontal system. Bouts of MVFR/IFR ceilings and visibilities 
with showers/thunderstorms expected late Sunday night into Monday afternoon. 
Deepest moisture and main band of precipitation expected to push offshore late 
Monday afternoon improving flight conditions. MVFR ceilings and a few showers 
possible Monday night into Tuesday as middle and upper lows move through the region. 
Mainly VFR thereafter as high pressure builds in. 


&& 


Marine... 
as of 315 am Sat...weak 1018mb surface high sitting near the central obx 
this morning. This is leading to highly variable wind directions but 
speeds at or below 10kt. Expect winds to remain light and trend more SW/S 
through early afternoon as high pressure begins moving offshore...with local 
sea breeze influences likely near the coast with well above normal 
temperatures anticipated inland. Main issue today will be lingering east-northeast 
swell energy that is still flirting with small craft range at 
Diamond Shoals. Looking at upstream buoys which are all much lower 
than 41025 I plan on dropping the Small Craft Advisory for the central waters this 
forecast...and expect this wave component to drop to at or below 4ft through 
this afternoon. Good boating conditions then expected through tonight 
into sun with modest southerly winds and seas mainly at or below 3ft. 


Deteriorating marine conditions still expected Sun night through Monday 
as next frontal system impacts the region. Fairly good confidence 
that especially our central and southern waters will see small craft seas from 
the associated short period southerly wave system late Sun night and especially 
Monday. Probably will be a brief period of small craft range winds as 
well but there remain some differences in the models so less 
confidence with that. The best potential for spurts of Small Craft Advisory S/SW 
winds appears to be from about 9z Monday through 00z Tuesday. Only change to 
forecast beyond Monday/day 3 was to increase winds a category for 
Tuesday/Tuesday night as models actually in better agreement that time frame 
than Monday...with near Small Craft Advisory range westerly winds developing south of 
deepening low pressure north of the area. Both the 00z GFS and European model (ecmwf) are 
showing a front moving through Wednesday night with northerly winds developing by 
Thursday. Our official ndfd grids are showing southerly winds this time frame 
based on yesterdays guidance...and will let day shift evaluate if a 
change is needed if this trend continues. 


&& 


Mhx watches/warnings/advisories... 
NC...none. 
Marine...none. 


&& 


$$ 
Synopsis...jbm 
near term...jbm 
short term...jbm 
long term...jbm 
aviation...mw 
marine...mw