Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

FXUS61 KILN 200613

Area Forecast Discussion
National Weather Service Wilmington OH
113 AM EST Sat Jan 20 2018

High pressure will push off to the east through tonight.
Developing southerly flow will lead to a warming trend through
the weekend, along with a chance of rain Saturday night into
Sunday. A better chance of rain will overspread the region
through the day on Monday as a cold front approaches from the


Skies are mainly clear with some increase in cirrus noted well 
ahead of low pressure developing on the lee side of the Rocky 
Mountains. Meanwhile, the surface pressure gradient should stay
tight enough tonight to limit decoupling and help keep winds up
somewhat. This is making a tricky temperature forecast with 
mainly clear skies early, snow still on the ground, and some 
question about how fast/much the winds will decrease. Will 
generally keep lows tonight from the upper 20s in the northeast
to the lower 30s in the southwest.


Southwest low level flow will continue through the day on 
Saturday. The models are in decent agreement bringing some 
better low level moisture in from the southwest through the 
afternoon. Initially the low level moisture is fairly shallow, 
but it will gradually saturate near and below 850 mb through 
Saturday evening. Forcing is pretty minimal, but given the weak 
WAA, this may be enough to produce a few light showers and/or 
drizzle. Will cover it at this point with a slight chance of 
rain developing later Saturday afternoon and then increasing 
into chance category Saturday night. In the WAA pattern, highs 
on Saturday will be in the low to mid 40s with lows Saturday 
night in the mid to upper 30s.


Surface low to develop over the central plains with the Ohio 
Valley in the warm sector. Weak isentropic lift may lead to a 
few rain showers Sunday. Will limit pops to chance category with
the best chance north. Expect temperatures to be around 10 
degrees above normal, with highs Sunday from the mid 40s north 
to the lower 50s south.

Mid/upper level low and deepening surface low to eject northeast 
from the plains into the upper MS VLY Monday and the Great Lakes 
Monday night into Tuesday. Moisture increases across the area ahead 
of an associated surface cold front that sweeps east through the 
area Monday night. Will continue to ramp pops up to categorical 
Monday. On the warm side of the system, temperatures look to be 10 
to 15 degrees above normal with highs Monday from near 50 northwest 
to the upper 50s southeast.   

With upper low tracking through the Great Lakes, a chance of 
precipitation will linger into Tuesday with rain changing to snow. 
The best chance will occur across the north counties, closer to the 
upper lows. Temperatures turn closer to normal with highs Tuesday 
from the mid 30s northwest to the lower 40s southeast.

In the wake of this system surface high pressure to build across the 
region In the Wed/Thu time frame. This feature will provide dry 
weather for the middle of next week. Temperatures will continue 
close to normal with Wednesdays highs from the mid 30s north to the 
lower 40s south. 

Temperatures will moderate slightly Thursday with highs from the 
upper 30s north to the mid 40s south.  

A southerly flow will develop on the backside of retreating high 
pressure for the end of the week. Moisture will increase with a 
chance of rain developing later Friday. Temperatures to warm up 
above normal with highs from the mid 40s northwest to the lower 50s 


VFR conditions will be found for the first half of the forecast
with wind shear to 40-45kt during the predawn hours. Cirrus
spilling in from the northwest and thickening will be the rule
until ssw surface winds advect in a 2000-2500' stratus deck
in the very late morning in the southwest to the afternoon in
the northeast. Models are showing light QPF over the region
later today and this evening, but this appears to be primarily
from the high moisture content in the lowest few thousand feet
and general convergence/upglide. With a lack of a distinct
forcing mechanism, have not included any sprinkles in the
forecast, though any that occur will likely be VFR vsbys
underneath the MVFR cloud deck. 

OUTLOOK...MVFR cigs expected through Sunday night. MVFR cigs 
and vsbys in rain possible Monday, along with 25kt gusts.





National Weather Service Glossary of Abbreviations