Rochester, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

855
FXUS63 KARX 251826
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
125 PM CDT Fri Jul 25 2025

.KEY MESSAGES...

- A smattering of weekend storm chances - but the higher
confidence/probabilities lie with Sunday night.

- Hot Sunday-Monday. Heat indices could top 100 degrees. Heat
Advisories possible for portions of the area.

- Cooling down for a few days next week (highs in the 70s for most).

&&

.DISCUSSION...
Issued at 125 PM CDT Fri Jul 25 2025

> WEEKEND STORM CHANCES: locally, higher chances currently focused
on Sunday night into Monday morning.

Various ripples in the upper level flow are progged to move mostly
west-east across the upper mississippi river valley this weekend.
Generally, the favored tracks are across northern parts of the
region. However, a west-east running sfc warm front will also be in
play, likely wavering somewhere across central MN/central WI. In
addition, where convection fires and then moves...leaving residual
outflow boundaries and then an MCV...will work to modify the
environment - and where later convection will be more likely. Ample
uncertainties and may not become relatively "clear" until 12 hours
out.

That said, there has been reasonable consensus for a higher storm
threat Sunday night into Monday morning locally. Shortwave trough
and low level jet interaction could/would spark convection over
central MN, moving east/southeast. How far southward these chances
would extend is unclear as a sizable portion of the guidance holds
the shower/storm threat north of I-94. However, there is a subset of
the models/ensembles that slide the MCS southeast across the bulk of
the forecast area. Too much uncertainty to lean the forecast one way
or the other and will hold with the model blend. Ample instability a
loft but wind shear limited, especially with low level inversion in
place. Depending on the timing, some stronger storm risk. Warm cloud
depths and increasing sfc PWs would support locally heavy rain.


> HEAT SUNDAY-MONDAY: heat indices of 100+ degrees possible/likely.

Upper level ridge building/increasing heights as we move through the
weekend, with heat and humidity pooling northward across the upper
mississippi river valley. A couple "steamy" days are promised Sun-
Mon via the variety of models. Not overly anomalous though - pushing
1+ for 850 mb temps in the NAEFS and EC while EFIs "only" at 0.5 to
0.6. The saying "it`s not the heat, it`s the humidity" is very
applicable here. While highs are currently forecast to top out in
the upper 80s to lower 90s, sfc Tds are expected to climb into the
lower to mid 70s - resulting in heat indices for Sun/Mon of 100+
degrees. Heat advisories are possible/probable for portions of the
forecast area in this time frame - favored along/south of I-90.

One caveat to the heat - movement/placement of the any mcs and their
resulting mcv (for later afternoon storm trigger). Pcpn/related
clouds obvious impediments to high heat. With uncertainties on where
the storm complexes would develop/move - will hold with the current
temp outlay - but some adjustments may be needed


> NEXT WEEK: cooling down for a few days. Spotty rain chances.

GEFS and EPS are both in favor of amplifying an upper level ridge
over the west coast while a trough/closed 500 mb digs across
southeastern Canada. All WPC clusters support this. This would place
the upper mississippi river valley under a cooler, northwest flow. A
few perturbations/convectively enhanced shortwaves could bring
periodic shower/storm chances - although timing/location
disagreements of these small scale features in the long range
guidance keeps predictability low.

After the hot start to the new week, temps look to drop back below
the seasonable normals. Over 75% of the GEFS and EPS members top
highs out in the 70s for the mid/latter part of the work week.

Some suggestion that the upper level pattern will be changing by the
following weekend, with that west coast ridge tracking over the
plains state. A return to summery heat would follow.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1234 PM CDT Fri Jul 25 2025

Diurnal cumulus has developed this afternoon around 2-4kft and will
continue through the evening, resulting MVFR ceilings where cumulus
is lowest and most abundant (primarily central Wisconsin). Early
Saturday morning, showers and thunderstorms move northeastward from
the central Great Plains, but should largely stay south and east of
a line from CCY to DLL providing just a glancing blow to our area.
Cloud coverage increases overnight associated with these
showers/storms, bringing the potential for MVFR/IFR ceilings to
areas along and south of I-90 including the TAF sites.

&&


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

&&

$$

DISCUSSION...Rieck
AVIATION...Falkinham