Rochester, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

368
FXUS63 KARX 140850
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
350 AM CDT Mon Apr 14 2025

.KEY MESSAGES...

- Windy conditions are expected today with gusts to around 40
  mph. This afternoon into tonight, some light showers appear
  likely with a bit of snow potentially mixing in north of I-94.

- Next shot for widespread rain comes later Thursday into
  Friday. Thunderstorms appear possible during this period as
  well. If everything comes together, severe storm potential
  would be present, but this appears unlikely at this time.

&&

.DISCUSSION...
Issued at 349 AM CDT Mon Apr 14 2025

Windy today with light showers this afternoon into tonight:

08z WV satellite reveals an upper low over the MN Arrowhead with
GOES satellite detections estimating a 95-100 knot 300mb jet
extending from NE to central WI. At the surface, cold front is
pushing through the area.

Today, expect windy conditions as 30-40 knot winds at 700/850/925mb
overspread the forecast area. Progged soundings have continued their
slight downward trend with winds at the top of the boundary layer
with these now largely below 38 knots. Given this trend toward
sub-advisory gusts and the likelihood of overcast skies inhibiting
mixing processes, have refrained from issuing a Wind Advisory.
Nevertheless, expect some gusts to around 40 mph from mid-morning
through the afternoon hours.

Late this afternoon next upper wave, currently over NE MT, will dive
southeastward over the region. This wave should bring some mid-level
moisture along with it and cool the mid-levels just a bit. This, in
addition to the low level  cold advection regime, should lead to
steep low level lapse rates with about 50 J/kg of CAPE, all of this
instability through a near saturated 700-900mb layer. Thus, current
thinking is that shallow open cellular post-frontal convection is
likely (60-70%) late this afternoon into tonight. Given expected
shallow nature of this convection, have kept QPF values minimal
while boosting PoPs. For areas north of I-94, could get a bit of
snow mixing in as temperatures fall after sunset but am not
expecting any impacts aside from brief reductions in visibility.

Widespread rain, chance for severe thunderstorm potential Thursday
into Friday:

THursday into Friday, as southwesterly flow aloft sets up, a
shortwave or two looks to eject downstream in this flow. With a
surface high present in the eastern Great Lakes in the wake of a
departing upper trough, southerly moist advection should be
sufficient for widespread showers and at least a few thunderstorms
to develop. While guidance continues to show a good deal of spread
on exact timing, best bet for precip at this time looks to be the
nighttime hours Thursday evening, when 850mb thetae advection alone
should lead to at least some light precip. On the subject of timing,
should sufficient moist advection occur early enough on Thursday and
a shortwave arrives during the late afternoon/evening, some severe
thunderstorm potential would be present given the large amount of
deep shear in place - 14.12z LREF suggests at least a 50 percent
chance for 50 knots of sfc-500mb bulk shear across the southern half
of the CWA. In fact, even if surface based storms don`t pan out
given late arrival of moisture, 14.00z GFS would support a risk for
elevated thunderstorms capable of producing large hail given MUCAPE
values around 1500 J/kg, largely uncapped but originating at
around 800mb. All that said, whether surface based or elevated, best
potential for sufficient instability for severe storms looks to
remain to our south at this time. Will continue to monitor this
period closely.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1005 PM CDT Sun Apr 13 2025

VFR ceilings fl050-100 will give way to partly cloudy skies a
winds strengthen from the west. MVFR ceilings are progged to
increase especially after 12Z and last through the early
afternoon with some patchy light rain/showers. Ceilings become
VFR in the afternoon, however more MVFR ceilings return Monday
evening. West winds increase 10 to 20kts and then 15 to 25kts
with stronger gusts 25 to 35kts Monday.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

$$

DISCUSSION...Ferguson
AVIATION...Zapotocny