Area Forecast Discussion Issued by NWS La Crosse, WI
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FXUS63 KARX 050427
AFDARX
Area Forecast Discussion
National Weather Service La Crosse WI
1027 PM CST Thu Mar 4 2021
.SHORT TERM...(This evening through Friday)
Issued at 239 PM CST Thu Mar 4 2021
Another quiet, sunny, seasonably warm day across the region today
as high pressure remained in control. Early afternoon
temperatures were generally in the 40s, though areas north of I-94
were struggling to get out of the 30s being closer to the cool
high. Once again the main forecast concern in the short term will
be potential fog/stratus development. For tonight, model soundings
show some slightly enhanced winds just above the surface and some
mid-level clouds, both of which would preclude fog development.
In addition, the normally aggressive HREF shows much lower
probabilities for visibility reductions tonight as compared to
previous nights. For Friday, some slightly cooler air aloft will
be creeping in, but even so, we`ll remain seasonably warm with
highs in the 40s to perhaps lower 50s again.
.LONG TERM...(Friday night through Thursday)
Issued at 239 PM CST Thu Mar 4 2021
The warming trend continues through the long term as upper level
ridging gradually slides eastward, with 850 mb temperatures across
the area getting back above 0 C by Sunday. In fact, the NAEFS
mean suggests 4+ C would be possible somewhere at least near the
area Sunday, which would be good for near the 90th percentile of
climatology. High temperatures will in turn be on the rise, with
guidance suggesting widespread 50s on Sunday and further increases
into the early to middle part of next week. That said, event the
high end of guidance has been too cool for the past few days,
especially Wednesday when several places topped out several
degrees above even the 95th percentile of guidance (a few spots
were higher than the overall maximum). Therefore, have continued
upward trend from guidance through Wednesday. Latest guidance
would suggest Tuesday will be the warmest day quite a few places
hitting 60 degrees and the higher end of the EPS suggesting mid
60s for some.
Otherwise, still looking dry through at least Monday and probably
Tuesday, despite some weak shortwave energy sliding through just
east of the forecast area on Saturday and to the north on Sunday.
The Sunday energy will also be dragging a weak surface boundary
through, but still not enough to produce any precip...maybe just
some increased cloud cover. Still looking likely that we see rain
sometime late Tuesday afternoon into Wednesday, but still a fair
amount of spread on exact timing. The general idea is that large
scale upper level troughing will start to move into the western
CONUS and some weak energy will spin up a surface low over
northeast Colorado. Resultant strengthening southerly flow and
warm air advection along with moisture transport pointed into the
area could lead to some shower development Tuesday evening.
Meanwhile, a surface boundary will be sagging southward toward the
area and a stronger bit of shortwave energy will be ejecting out
of the desert southwest and the aforementioned surface low will
move through the forecast area Wednesday, bringing more widespread
showers. Most guidance also shows several hundred J/kg of MUCAPE,
so will probably have a few rumbles of thunder as well. Could see
some light snow on the back side as the system departs Wednesday
night, though some guidance holds on to precip into Thursday
morning.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1027 PM CST Thu Mar 4 2021
VFR conditions will continue with little change in overall
conditions. Surface ridge centered over Wisconsin with light flow
and relatively dry air. Some moisture in mid levels is leading to
development of some mid layer ceilings again tonight but those
should move on out Friday morning.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...DAS/CA
LONG TERM...CA
AVIATION...Shea