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000 
FXUS61 KILN 201132
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
632 AM EST Wed Nov 20 2019

.SYNOPSIS...
Weak high pressure will bring dry weather today. A cold front 
moving in from the northwest will provide a chance of showers 
Thursday and Friday. More precipitation will be possible 
Saturday when low pressure is forecast to travel across 
Tennessee.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The weather map today will have surface high pressure 
developing under a northwest flow aloft. Even with the center of
the high passing across Ohio, ample low level moisture trapped 
under an inversion is causing BR to form early this morning, 
while skies remain mostly cloudy, given light winds and minimal 
mixing. BR should dissipate by mid morning, while cloud cover
lingers through today under the persistent inversion. No
measurable precip is expected due to the lack of forcing and 
deep moisture, though patchy drizzle cannot by ruled out. 
Temperatures inhibited by the cloud cover should reach the upper
40s this afternoon.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Though low level moisture may finally diminish tonight as the
high travels east, mid and high clouds will be moving in ahead 
of the next front, keeping skies mainly cloudy.

For Thursday, showers are likely to develop ahead of a cold
front approaching from the northwest. With models showing rather
weak moisture transport and disorganized convergence, look for
precip amounts under a tenth of an inch, concentrated mainly
over northwest counties closer to the bulk of moisture and
forcing.  

With the front arriving a bit later than indicated on earlier
model runs, temperatures may rise a bit higher than previously 
thought in warm advection ahead of the front, with highs
reaching the mid 50s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
The extended period starts with a cold front located just to the 
west of the region. This front will push through the fa Wednesday 
night. Drier trend of frontal passage with this system, that started 
last night has continued. Highest PoPs still look like they occur 
across the northern counties, with lower PoPs towards the southeast 
counties.

Models have remained consistent on Friday in pushing the northern 
portion of the front into the Appalachians, while hanging it up in 
Kentucky. This will bring drier air into the north, but rain chances 
will linger all day for the south. Highs on Friday will be slightly 
below normal behind the front, ranging from the mid 40s in the 
northwest to the mid 50s in the southeast.

Models agreement continues Friday night as H5 energy swings out of 
the Rockies Friday night. Meanwhile, they dry out the fa Friday 
evening, then start to bring some pcpn back into the far south 
towards sunrise Saturday ahead of a surface low.  

The surface is forecast to lift through eastern Kentucky into 
eastern Ohio on Saturday. All models are consistent in pushing pcpn 
up across the region Saturday. There are still differences in how 
much cold air will be in the northern half of the fa, and of course 
this will affect the ptype. Have a mention of chance of snow for 
early Saturday morning for the north and rain/snow mix farther 
south. Precipitation should change to rain on Saturday as the 
atmosphere warms during the day.

The system pulls away quickly Saturday night, allowing high pressure 
centered way down in eastern Texas to begin to build in.  It will 
bring dry weather for the rest of the extended.  Temperatures will 
be a about 5 degrees below normal on Sunday, with highs in the upper 
40s to lower 50s. A warming trend will Monday into Tuesday will push 
highs to near to slightly above normal. 00Z ECMWF has just come in 
with a chance of pcpn for Tuesday, but it is the outlier, so will 
discount it for now.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
Low level moisture persisting under weak high pressure will
result in less than ideal flight conditions. CVG will have IFR 
ceilings that may not improve for several hours as moisture 
stays trapped under an inversion in the presence of light winds.
Other sites can expect MVFR conditions to linger for a few more
hours. We may see improvement to VFR this afternoon as drier 
air begins to work in behind the high. MVFR conditions may then 
return to CVG LUK and ILN tonight. CVG should see VFR with 
increasing south winds after 12z Thursday.

OUTLOOK...MVFR/IFR ceilings likely Thursday night and again 
Saturday through Sunday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$
SYNOPSIS...Coniglio

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