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Area forecast discussion 
National Weather Service Wilmington Ohio
1009 am EDT Tuesday Apr 21 2015

a strong low pressure system over the Great Lakes will bring very
windy conditions today along with a chance of showers at times
tonight into Wednesday morning. Drier conditions are expected from
Wednesday afternoon through the rest of the week...with breezy
afternoons and cool temperatures. Another chance of rain will
arrive on Saturday.


Near term /until 6 PM this evening/...
deep mixing today will allow gusty winds to strengthen further and
also mix out dew points. A middle level short wave will pass across
the area this afternoon. This will bring an area of clouds.
Cannot rule out a few sprinkles out of this middle deck. But think it
will be too dry for measurable precipitation. Forecast highs look
reasonable at this point.


Short term /6 PM this evening through Friday/...
precipitation is expected to move into the region (or perhaps
develop over the forecast area) on Tuesday night into Wednesday
morning. Although there are some model differences with regards to
the intensity and layout of the precipitation...the overall timing
appears to favor the 06z-15z time frame for the iln forecast
area...ahead of a shortwave and a surface cold front. Although
this front shows up nicely on mslp plots...the wind shift and
change in air mass are not especially notable. Instability (even
elevated) will be hard to come though thunder is not an
impossibility with this setup...the chance seems very low.

Once this front passes...very similar conditions are expected for
the rest of the week...with northwest flow and cool weather. Ohio
is likely to remain in between areas of enhanced moisture from the
northern and southern streams...leading to generally sunny
conditions until Friday night.

Temperatures on Thursday and Friday morning may be cool enough for
frost...but moisture and wind forecasts are not as favorable.
Thus...frost will not be included in the grids or severe weather potential statement.


Long term /Friday night through Monday/...
some deeper moisture will be pulled up toward our area on
Saturday ahead of short wave energy moving out of The Rockies.
While the best forcing/moisture associated with this will remain
to our south...some precipitation could sneak up into at least southern
portions of our forecast area early in the weekend. This may also allow for a
slight modification in temperatures with highs pushing into the
upper 50s to lower 60s by the end of the long term period.


Aviation /14z Tuesday through Saturday/...
large scale upper level low centered over the western Great Lakes
this morning will move slowly east through the taf period. Embedded
disturbances rotating around the low will affect our region from
time to time.

For today...strong surface low pressure will remain north of the
Great Lakes. Meanwhile...a cold front will approach the region
from the west. The increasing surface pressure gradient combined
with deep mixing will result in windy conditions from middle morning
into early evening. Winds will veer from a southwest to a
west/southwest direction with wind gusts in the 30 to 40 knot
range. Models continue to indicate that some moisture in the low
to middle level will develop/advect northeast into the region by this
afternoon. This cloud layer could become convective enough to
produce a few sprinkles or light showers...mainly along and south
of the Ohio River.

For of those embedded disturbances mentioned will
dig southeast into our area. This feature will team up with
frontal convergence from the advancing cold front to bring a
threat of showers to the taf sites between 06z and 12z. There
could be some pockets of MVFR visibilities associated with the
more robust showers.

Outlook...gusty west to northwest winds up to 30 knots expected
Wednesday afternoon into early evening.


Iln watches/warnings/advisories...
Ohio...Wind Advisory until 7 PM EDT this evening for ohz026-034-035-
In...Wind Advisory until 7 PM EDT this evening for inz050-058-059.


near term...
short term...hatzos
long term...jgl

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