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Area Forecast Discussion (AFD)

Issued by Wilmington, OH (ILN)

FXUS61 KILN 202014

Area Forecast Discussion
National Weather Service Wilmington OH
414 PM EDT Sun May 20 2018

An east-west front extending across the region will lift north
on Monday as low pressure moves across the lower Great Lakes. As
the low progresses east, a trailing cold front will cross the
area late Monday night into Tuesday. High pressure will build in
behind this front. 


Weak boundary continues to bisect the forecast area. Dew points
are pooled along this which also corresponds with the cumulus
field. Forcing is quite weak, but there remain indications that
some convection could develop late this afternoon and continue
into evening. DCAPE has been increasing, so if storms can form,
then there will be the potential for strong to damaging wind
gusts through the remaining daylight hours. 

Additional elevated showers and thunderstorms may develop
generally along the I-70 corridor in the overnight hours. MOS
seems to have a reasonable handle on lows. 


Boundary will lift north on Monday as low pressure moves towards
the lower tip of Lake Michigan. Scattered to numerous showers
and thunderstorms will occur with this boundary. Some convection
will remain possible in the warm sector with better coverage
late in the day into the evening along a pre-frontal trough.
There is quite a bit of uncertainty in terms of how much
instability will occur in the warm sector as well as the timing
of the pre-frontal trough. A later arrival of the trough will 
mean that instability will be starting to wane as stronger-
forced storms move in to the area. Any of the more robust 
storms could result in a damaging wind threat during the
afternoon and evening. Showers and some thunderstorms will
remain possible through the remainder of the night. 

Generally went a bit above guidance for temperatures. 


Active weather pattern to continue through early next week with 
ILN/s FA on the periphery of mid/upper level ridging. 

Mid level shortwave to induce a surface wave that tracks through the 
area Monday night and Tuesday. This will allow an associated surface 
front to drop southeast through the Ohio Valley Tuesday. This will 
offer a continued threat for showers and thunderstorms. Warm 
temperatures to continue with Tuesdays highs from the upper 70s 
northwest to the lower 80s southeast. 

Northwest flow aloft to develop with surface high pressure building 
into the Great Lakes. A lingering chance for showers/thunderstorms 
will persisting the southeast early Wednesday, otherwise expect dry 
weather. Expect highs Wednesday in the upper 70s to lower 80s.

The surface high will build southeast with continued dry weather 
Thursday. Above normal temperatures with highs from near 80 north to 
the lower/middle 80s south. 

Southerly low level flow develops on the backside of retreating sfc 
high pressure Friday with mid level ridging building into the Ohio 
Valley. Temperatures will warm up with highs in the lower and middle 

Mid level flow backs ahead of a developing trof with moisture 
increasing Friday night. Will mention chance pops for showers and 
thunderstorms Friday night west and across the entire area Saturday. 
Warm temperatures to continue with highs Saturday generally in the 
middle 80s.


VFR conditions are expected through at least the first half of
the TAF period outside of any convection. And at this point, the
probability of a storm impacting any of the terminals is too low
to include lower conditions in the forecast. But VC has been 
used where appropriate to indicated when the better chance of 
precipitation is. After 06Z some mist/fog may develop and 
reduce visibilities. In addition, stratus is possible near the 
weak boundary remaining across the area. Conditions will improve
to VFR late in the period.

OUTLOOK...Thunderstorms possible through Tuesday.




LONG TERM...Haines