Strong Wind in Missouri, December 27, 2018

Area Forecast Discussion
National Weather Service Paducah KY
446 AM CST Thu Dec 27 2018

.UPDATE...
Issued at 436 AM CST Thu Dec 27 2018

Updated for 12z aviation only.

&&

.SHORT TERM...(Today through Saturday night)
Issued at 151 AM CST Thu Dec 27 2018

The models have been locked into this storm event for today and
tonight for more than seven days. So confidence is high in rain
today. Also it will be a windy day with or without any storms and
the models have hinted at that for several days.

An upper level closed low centered near the Oklahoma panhandle will
make its way northeastward toward the great lakes today. It will
have a surface reflection of a low which will be nearly vertically
stacked. The low will have an attendant warm front and cold front
extending southward. The warm front will lift through our area first
bringing unseasonably warm air to the region. Even though we start
the day with a major inversion preventing any surface based
instability we will have K index values near 30 but showalters
values remain positive through the morning hours. By this afternoon
the inversion starts to erode and we develop weak elevated CAPE
approaching 100 j/kg2 and LI's of negative one or so. K index values
exceed 30 with Showalters going negative mainly east of the Ohio and
Wabash Valleys. This is as the warm front lifts north and the cold
front hangs back to the west...placing us in the warm sector for a
brief period. This will at least bring a chance of thunder this
afternoon and evening. Severe is not anticipated at this time.
However we will have 35 to 45 knot winds between 800 feet and 1500
feet respectively. So any convection could tap into those winds and
bring some significant wind gusts to the surface. Therefore a wind
advisory has been issued for today and tonight.

By Friday the fronts will have exited the area bringing much cooler
temperatures back to the region. High pressure will build in over
the central plains keeping a northwest wind over the region...but
much not a strong or gusty wind. This will mainly affect
temperatures by cooling them down into the 40s for highs this
weekend. The blend has been trying to put a wintry mix Saturday
night after midnight. However the latest deterministic runs are
indicating a very weak signal with this surge of moisture from the
Gulf. Most models are trying to keep it south of the state borders.
We will wait for the next blend and collaboration to better define
this period.

.LONG TERM...(Sunday through Wednesday)
Issued at 151 AM CST Thu Dec 27 2018

Relatively good model agreement lends to above average confidence in
the long term portion of the forecast. The only exception may be
with the early week system, which probably needs another model run
cycle or two to better enhance confidence.

A storm system taking shape over the southern Plains during the
weekend is forecast to quickly lift northeast into the Ohio Valley
by Monday. As it does, it will provide ample forcing for ascent of
Gulf moisture to yield the potential for rain across our region late
in the weekend and early next week. Over the past few cycles, the
trend in forecast models has been warmer and wetter. As a result,
most if not all the precipitation is expected to be in the form of
rain. The outlier CMC does bring the onset of rain into southern
counties late Saturday night, which is earlier than the preferred
GFS/ECMWF blend. Temperatures may be close to the freezing mark at
that time, but probably just warm enough for rain.

The consensus blend holds off the onset of rain until much later on
Sunday, and if the latest GFS/ECMWF are taken verbatim, rain may not
begin in earnest until Sunday night. Rain is forecast to continue
into the first half of Monday, then taper off from west to east by
Monday afternoon. Forecast precipitation amounts range from one half
to 1.5 inches, with higher totals across western Kentucky.

Even though the daytime hours of New Year's Eve look wet, New Year's
Eve itself is looking dry at this point as the storm system shifts
east of the area. The passage of a cold front Monday night into
Tuesday will bring much colder air into the region as high pressure
builds south from Canada. While highs Sunday and Monday are forecast
in the 40s and 50s, highs by Wednesday are only projected in the
lower to middle 30s. Lows should cool from the 30s and 40s over the
weekend into the upper teens to lower 20s by Tuesday and Wednesday
nights.

&&

.AVIATION...
Issued at 436 AM CST Thu Dec 27 2018

Removed the llws since winds are gusting fairly well at the
surface. Plan on bringing cigs into the MVFR range right out of
the gate for CGI and PAH. If there not that low they soon will be.
Left vfr cigs in EVV and OWB for a good part of the morning. We
may even get some LIFR cigs after 00z Friday. Keep rain in as a
vsby obstruction all day and relax the rain chances overnight.
Rain should lift out the region toward the end of the forecast.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Wind Advisory until 3 AM CST Friday for ILZ083-085>094.

MO...Wind Advisory until 3 AM CST Friday for MOZ087-108>112-114.

IN...Wind Advisory until 3 AM CST Friday for INZ081-082-085>088.

KY...Wind Advisory until 3 AM CST Friday for KYZ001>022.

&&

UPDATE...KH
SHORT TERM...KH
LONG TERM...RJP
AVIATION...KH

Hazardous Weather Outlook
National Weather Service Paducah KY
303 AM CST Thu Dec 27 2018

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-
100-107>112-114-281000-
Jefferson-Wayne IL-Edwards-Wabash-Perry IL-Franklin-Hamilton-
White-Jackson-Williamson-Saline-Gallatin-Union-Johnson-Pope-
Hardin-Alexander-Pulaski-Massac-Gibson-Pike-Posey-Vanderburgh-
Warrick-Spencer-Fulton-Hickman-Carlisle-Ballard-McCracken-Graves-
Livingston-Marshall-Calloway-Crittenden-Lyon-Trigg-Caldwell-
Union KY-Webster-Hopkins-Christian-Henderson-Daviess-McLean-
Muhlenberg-Todd-Perry MO-Bollinger-Cape Girardeau-Wayne MO-Carter-
Ripley-Butler-Stoddard-Scott-Mississippi-New Madrid-
303 AM CST Thu Dec 27 2018

This Hazardous Weather Outlook is for portions of southern
Illinois, southwest Indiana, western Kentucky, and southeast
Missouri.

.DAY ONE...Today and Tonight

There is a slight chance of thunderstorms today and tonight. The
main hazard with any isolated storms would be strong gusty winds.
Dangerous lightning and locally heavy rainfall are also possible.
A Wind Advisory is also in effect Thursday, and ends Thursday
night. Refer to the Advisory for details.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.