Area Forecast Discussion
Issued by NWS La Crosse, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
FXUS63 KARX 171058

Area Forecast Discussion
National Weather Service La Crosse WI
500 AM CST Tue Jan 17 2017

.SHORT TERM...(Today through Wednesday Night)
Issued at 217 AM CST Tue Jan 17 2017

Water Vapor imagery/RAP 500mb analysis shows tightly wound mid-level
low (responsible for the Monday/overnight icy mess across our area)
spinning northeast through northern Illinois early this morning.
Radar was showing out area pretty much void of precipitation with
just hit/miss showers. Stretched deformation area between that
northern IL low and trough pushing southeast through MN was
producing a band of wintry mix precipitation from southeast MN into
northern WI. Otherwise...quite an icy mess left over across the area
from freezing rain. Some fog has formed overnight with light winds
and ample lower boundary moisture. Not really dense at this point,
but will be keeping a close eye on visibilities through this
morning. Temperatures across the area as of 2 am were in the
lower/middle 30s.

Aforementioned deformation forced mixed precipitation will drift
east across the area early this morning...affecting areas mainly
along and north of I-90 through mid-morning...then
diminishing/exiting the area by early afternoon. As such, and with
the morning commute in mind, will keep Winter Weather Advisory
headlines in tact until noon or until improvements are noted.
Portions of the area may be trimmed out of the headline if
improvements are noted. Otherwise, will have plenty of stratus to
contend with today with relatively mild mid-January highs in the 30s.

High pressure builds in tonight with stratus diminishing from west
to east. Temperatures expected to dip into the 20s. So, expect some
refreeze of melted off glaze/snow. This could cause some slick spots
on untreated roadways and sidewalks. High pressure remains in
control though Wednesday for partly cloudy skies and mild highs in
the 35-40 degree range...much needed to melt off/hopefully dry any
left over icy mess. Could see some refreeze problems again Wednesday
night from daytime melt-off as lows dip back into the 20s.

.LONG TERM...(Thursday through Monday)
Issued at 217 AM CST Tue Jan 17 2017

January thaw will be in place through the period with highs in the
upper 30s/lower 40s. Am a bit concerned for stratus/possible fog
potential given the thaw and release of moisture into the lower
boundary layer. As such and unfortunately, looks to be mostly cloudy
through the period. Also, appears there will be on/off precipitation
chances through the period as increasing southerly flow sets up over
the region.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 500 AM CST Tue Jan 17 2017

Wintry mix exiting east this morning, diminishing as it does. Mostly
just a -fzdz/dz threat concern for krst/klse for an hour or two
around 12z. Sub 1 kft cigs should stick around the better part of
the day, with a slow inching upward toward the evening. Expect
clearing toward 06z tonight as a ridge axis moves in from the west.
Mostly mvfr vsbys into the weekend, but a smattering of 2sm or less
over southern MN. Will hold onto some IFR vsby potential early this


WI...Winter Weather Advisory until Noon CST Today for WIZ017-029-

MN...Winter Weather Advisory until Noon CST Today for MNZ079-086>088-

IA...Winter Weather Advisory until Noon CST Today for IAZ008>011-018-



AVIATION.....Rieck is the U.S. government's official web portal to all federal, state and local government web resources and services.