Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 030555
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
1155 PM CST Sun Mar 2 2014
ISSUED AT 1155 PM CST SUN MAR 2 2014
The AVIATION section has been updated for the 06Z TAF issuance.
UPDATE ISSUED AT 925 PM CST SUN MAR 2 2014
Just overhauled the forecast for the remainder of the storm. Now
have no more freezing rain. Up to 2 inches of sleet will be likely
over the southern half of the region this evening, and 2 to 3
inches of snow will be possible along the I-64 corridor. After
midnight the moderate to heavy snow will set in areawide, but the
heaviest accumulations will be in the south according to the 18Z
GFS and 00Z NAM. The updated grids have alot of the 00Z NAM in
them. Much of west Kentucky could see 6 to 9 inches of sleet and
snow total before it ends Monday morning.
The precipitation will be ending from the north quickly after
09Z, and will linger past 12Z over the entire southern half of the
area. Therefore have made the appropriate adjustments to the WSW
product. The ice storm warning has been cancelled and replaced
with the Winter Storm Warning through 18Z. All of southeast
Missouri, except Perry county will continue through 18Z. The
warning will now expire at 12Z for southwest Indiana and adjacent
portions of southern Illinois.
UPDATE ISSUED AT 731 PM CST SUN MAR 2 2014
No fun trying to keep up with or make sense of continually
changing precipitation types this evening. Just updated the public
grids to try to catch up to the latest developments through the
evening. It looks like additional icing over the far southeast
corner of the forecast area should be under a quarter inch which
should keep that area under a half inch of glaze on elevated
objects. Elsewhere, should see sleet dominate much of the area
with a gradual transition to snow from northwest to southeast
through the evening. Up in the Du Quoin and Mt Vernon areas, snow
will be the dominant precipitation type for the remainder of the night.
The heavy precipitation is just now surging northeast into the
area, and over an inch of liquid equivalent precipitation is still
expected tonight. All evidence from satellite observations is that
the upper-level low over the OK/TX panhandle region is actually
intensifying, and the models were consistently dampening it out as
it approached the area. This could lead to even more precipitation
than expected, and potentially heavier deformation zone snows
overnight into Monday morning. Could see several inches of snow
over the southern half of the area before it is done. Will tackle
this in an update later this evening.
.SHORT TERM...(This Evening through Tuesday night)
ISSUED AT 312 PM CST SUN MAR 2 2014
Plan on no changes to the current winter warnings now in place
over the region. It now appears that the greatest icing potential
will be limited mainly to locations of the southern
Purchase/Pennyrile in wrn KY. It seems as tho enough cold air has
worked into areas along the Ohio River to support mostly sleet
this evening. Still major questions on how quickly the sleet can
transition over to snow from nw to se tonight. This will likely be
the deciding factor on how much snow we get, esp in areas along
and just south of the Ohio River where precip amounts are likely
to be quite significant. Current thinking is that the snow line
will work south to along the Ohio River by around midnight, then
work its way into the srn Pennyrile by around 3 or 4 AM.
Latest satellite and radar trends suggest this system is really
getting its act together over AR this afternoon. Precip has
lightened up in many locations, but this should not fool anyone.
Heavy precip will likely move back into many locations overnight,
esp areas along and south of the Ohio River. Latest 18z NAM now
suggests an additional 1.5 to 2 inches of QPF between 21Z this
afternoon and 15z Monday from far se MO right through most of wrn
KY. Though will not go this extreme right now, still could be more
extensive icing through the evening over the srn Pennyrile and
Purchase of wrn KY, with another round of heavy sleet up along the
OH River. Farther north, we should see a change to snow this
Around midnight, we expect the sleet to transition over to snow
over far se MO and northern parts of wrn KY. The snow should then
continue within the deformation zone through around 7 or 8 AM.
This should allow for a good 6 hours of decent snow, and there
may even be localized banding in the deformation zone of srn IL
and wrn KY. Snow amounts in the 4 to 6 inch range could become
widespread, with locally higher accumulations within bands.
Northerly winds 20 to 30 MPH will cause considerable
blowing/drifting of what snow does fall. With sfc temps in the
teens, wind chill values could easily reach 0 to 10 below in many
locations by Monday morning.
Arctic high pressure following the system Monday night and Tuesday
will likely bring single digit temps at night with highs only in
.LONG TERM...(Wednesday through Sunday)
ISSUED AT 312 PM CST SUN MAR 2 2014
A rather uneventful weather pattern will take hold through the
remainder of the week. Stratified upper level flow will tend to keep
any weather systems either north or south of the immediate region
through Friday. The core of arctic high pressure will shift across
southeast Canada and the Great Lakes region into the Northeast by
Thursday. The forecast region will be on the southern periphery of
this high. As a result, expect unseasonably cold weather to start
the week. As the week progresses, the combination of slowly warming
temperatures and an increasing March sun angle should help to slowly
erode the snow and ice cover that will be in place at the beginning
of the week. After a prolonged period of sub-freezing temperatures,
expect highs to climb into the 30s on Wednesday, 40s Thursday, and
perhaps even near 50 by Friday.
By late week, both the GFS and ECMWF bring another piece of energy
east across the Plains with an approaching cold front. Both models
are not quite in agreement with respect to timing, but the general
idea yields our next chance of precipitation by the weekend. As a
result, we continue the slight chance of rain Friday night and
Saturday. At this point, temperatures appear warm enough to support
mainly liquid precipitation Friday night and Saturday. However,
temperatures may be cold enough by Saturday night for a mix of rain
ISSUED AT 1155 PM CST SUN MAR 2 2014
Snow has finally arrived all the TAF sites, and is expected to
continue through at least 12Z. It will come to an end 12Z-14Z. The
snow is expected to be moderate to heavy at times. KCGI and KPAH
should see the heaviest snow overnight as the upper-level storm
system passes just south of the area.
The big question behind the snow will be how long MVFR ceilings
will linger? There was quite a discrepancy between the model data
and the statistical guidance, so just tried to split the
difference between the two. Should see clearing from west to east
through the afternoon.
Definitely seeing some signal for fog development late in the
evening, as skies clear and winds become light. Did not mention it
at this time due to the length of the TAF, but it will likely be
added for the overnight hours at 12Z.
Winds are the strongest right now and will continue steady at
these levels through the night. They will weaken gradually through
IL...WINTER STORM WARNING until Noon CST Monday FOR ILZ085>094.
WINTER STORM WARNING until 6 AM CST Monday FOR ILZ075>078-
MO...WINTER STORM WARNING until Noon CST Monday FOR MOZ086-087-100-
WINTER STORM WARNING until 6 AM CST Monday FOR MOZ076.
IN...WINTER STORM WARNING until 6 AM CST Monday FOR INZ081-082-
KY...WINTER STORM WARNING until Noon CST Monday FOR KYZ001>022.