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000 
FXUS62 KILM 202307
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
607 PM EST Wed Nov 20 2019

.SYNOPSIS...
High pressure and seasonable weather will continue through 
Thursday before a warmup begins Friday. A cold front will move 
across the Carolinas over the weekend, with high pressure 
returning early next week.

&&

.UPDATE...
No significant changes to the forecast with this early evening
update.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
Surface high pressure and zonal mid level flow will keep things 
seasonable to very slightly cool through Thursday. Dewpoints will 
decrease slightly and there is currently no guidance that indicates 
any fog development. Forecast soundings are dry enough to completely 
clear skies overnight while they do show some increase in cirrus 
level moisture on Thursday. Surface high pressure suppresses to the 
south Thursday night allowing for weak return flow of mild and more 
humid air Thursday night. The resulting increase in cloud cover 
should once again preclude any fog development.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Elongated surface high south of the region and flattening mid-level 
pattern allow a weak cold front into the region later Fri. Front 
likely ends up stalled north and west of the area Fri night into 
Sat. Front trails low moving across southeast Canada and is 
displaced far enough that any cold push will have faded. Also 
working against the front will be a southern stream system moving 
from eastern TX into the TN Valley. Patchy light rain will be 
possible late Fri night, but better chances will be later Sat into 
Sat night. The TN Valley low moves into the Mid-Atlantic late Sat 
night, dragging a cold front through the region as the week ends. 
Strong warm advection sends highs above climo Fri with highs once 
again above climo Sat despite increasing cloud cover. Cold advection 
lags well behind the cold front Sat night. Cloud cover and wind will 
keep lows well above climo Fri and Sat night.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Surface high pressure and flat pattern aloft will persist through 
early parts of next week. Pattern aloft becomes more amplified mid-
week as 5h trough emerges from the Desert Southwest and lifts 
northeast. Abundance of deep dry air and minimal forcing will keep 
the region dry Sun through Tue night. Might start to see increasing 
rainfall chances on Wed, although at this point confidence is low. 
Cold front associated with deepening system in the Great Lakes may 
spread scattered showers across the area later Wed, but stacked lows 
tend to move slower than guidance expects and Wed could very well 
end up dry. Temps dip below normal Sun night and Mon on the back of 
modest cold advection. Air mass starts to modify later Mon and 
development of return flow and warm advection Tue into Wed pushes 
temps above climo for the middle of next week.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
VFR throughout the period. Clear skies with winds out of the north 
and below 5 knots overnight. The center of the sfc high will move 
overhead tomorrow and will create NE winds in the morning with light 
winds and varying direction possible in the afternoon. No aviation 
concerns expected.

Extended Outlook...VFR through Friday with showers and sub-VFR 
conditions possible this weekend.

&&

.MARINE...
Wind will remain northerly through early Thursday as high pressure 
is located north of the region. Later in the day as the high sinks 
southward wind will grow lighter and turn to the W or SW. Light S 
to SW flow will persist Thursday night as a weak coastal trough 
develops. 

Southerly flow will increase Fri into Sat as cold front approaches 
from the west. Tightening gradient will lead to winds in excess of 
20 kt at times late Sat into Sat night. Persistent southwest flow 
coupled with increased wind speeds could lead to a brief period of 
seas over 6 ft, requiring a short lived Small Craft Advisory late 
Sat night into Sun morning. Weak southeast swell Fri and Sat quickly 
becomes secondary to the dominant southwest wind wave around 5 
seconds. Offshore flow sets up Sun as high pressure builds in, but 
lack of strong cold advection and weakening gradient will allow for 
speeds gradually decreasing during the day before dropping under 10 
kt Sun night and Mon. Offshore flow helps drop seas to 2 to 4 ft by 
late afternoon Sun and to 2 to 3 ft on Mon. Southerly swell will 
linger Sun and Mon but a northwest wind wave will become the 
dominant feature.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.

&&

$$

SYNOPSIS...III

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