Area Forecast Discussion
Issued by NWS Twin Cities, MN

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
844
FXUS63 KMPX 251110
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
610 AM CDT Tue Jun 25 2024

.KEY MESSAGES...

- Scattered showers are expected tonight, but precip amounts will be
  light and no severe weather is expected.

- Next periods of unsettled weather will be Thursday night into
  Friday and again Monday into Tuesday next week.

&&

.DISCUSSION...
Issued at 319 AM CDT Tue Jun 25 2024

Eventually we got an MCS to form in the extreme instability
environment we had on Monday, but it got going over northwest
WI and made its way to Green Bay overnight, only impacting the WI
portion of our area to the north of I-94. Early this morning,
surface analysis shows a surface low near the southwest tail of the
MCS that developed. There are a couple of surface frontal
boundaries. The main cold front extends southwest from the low back
into central Iowa. This has the wind shift over to the northwest,
but the drop in dewpoints is an east/west boundary that was back
across central MN at 3am. This secondary boundary will continue to
sag south through the day and by the afternoon will meet up with the
cold front north of I-80 in Iowa. This means that through the
morning, our instability will be dropping appreciably. Although
we`ll have some lingering instability in south central MN, the
redevelopment of thunderstorms this afternoon will be well south of
the MPX area. Instead, we`re waiting on the shortwave currently over
southern Alberta for our next chance of rain. This will come through
central & southern MN tonight and most of the CAMs  show some
scattered showers associated with it. Although we`ll have this
forcing, by then, our moisture will be considerably lower and
instability almost non existent. So no severe weather is anticipated
and rainfall amounts will be light (less than a quarter of an inch).

We get high pressure and dry weather for Wednesday, but will get on
the backside of the high on Thursday, with moisture quickly starting
to return north ahead of the next shortwave that will pass along the
international border Thursday night. The trend in the highest QPF
being north and south of the MPX noted in the last couple of AFDs
continued with the 00z models overnight. We`re seeing higher QPF
with the better forcing up along the international border, with
another bullseye near the IA/MO border associated with the higher
moisture. Still, we`ll have favorable diffluent flow aloft move
through with the trough Thursday night, with widespread showers and
storms expected, but the forcing with this system continues to favor
any heavy rain issues being isolated at best. By then, all but the
lower MN and MS rivers will be on a downward trend and it doesn`t
look like the rainfall associated with this system will be
heavy enough to reverse those trends.

Next weekend still looks spectacular with dry weather and highs in
the 70s and lows in the 50s, but with the seasonably strong zonal
flow still in place, we won`t have to wait long for our next chance
of precip. That comes early next week. Guidance shows a shortwave
taking on a more negative tilt as it moves through the upper MS
Valley Monday night, so the resultant system will likely be a bit
stronger than what we see at the end of the week. We`re still a ways
out, but at this point the system early next week would be something
to keep an eye on from the severe weather and heavy rain
perspective. The flow will still be progressive though, so this
system does not look like it will linger into the 4th of July
holiday.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 600 AM CDT Tue Jun 25 2024

A much quieter 24-30 hours is in store with west to northwest
surface winds dominating. There will be a couple of chances for
showers, but neither look high enough to include in the TAFs.
The first comes late morning for RWF/MKT with activity currently
over SoDak working across the moisture gradient sliding south.
The second comes with the arrival of a stronger shortwave
overnight. In both cases, dry low level air, then a lack of
instability for tonight look to minimize our precip chances this
period.

KMSP...No additional concerns with a much needed TS free VFR TAF
period.

/OUTLOOK FOR KMSP/
WED...WED...VFR. Wind NW 5-10 kts.
THU...VFR. MVFR/-TSRA likely overnight. Wind S 5-10 kts.
FRI...VFR. MVFR/-TSRA likely mrng. Wind SW bcmg NW 10-15 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

$$

DISCUSSION...MPG
AVIATION...MPG