Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
315 PM CDT Fri May 14 2021

.SHORT TERM...(This evening through Saturday night)
Issued at 307 PM CDT Fri May 14 2021

Surface analysis this afternoon shows the Upper Midwest caught
between a pair of east-west stalled frontal boundaries, one just
north of the international border and a second from the mid-
Mississippi River Valley region westward across the Central Plains
into the Rockies. A weak surface low/trough feature is over far west-
central MN. Aloft, a pattern of weak troughing over the eastern
CONUS with weak ridging over the Rockies puts the Upper Midwest over
modest northwest flow, contributing to the influx of Pacific
moisture and cooler air over the region.

The western ridge will nudge a bit eastward tonight through
Saturday, which will also nudge the surface trough across MN and
into western WI during the day Saturday. As such, ongoing
precipitation scattered over the WFO MPX coverage area will be
mainly limited to eastern portions late Saturday into Saturday
night. The added moisture, which has taken the form of cloud cover
due to the pronounced dry layer in the lower 6-8 kft, has helped
keep convection in check but a few isolated thunderstorms have
finally popped in the far eastern Dakotas along the MN state line,
where sunlight is most prevalent to aid in heightened instability.
While SPC has eliminated the Marginal Risk, some thunderstorms with
sub-severe hail cannot be ruled out due to steepened lapse rates
with the colder air aloft.

Any thunderstorms will dissipate late tonight with no additional
thunderstorms expected with the possible precipitation over eastern
parts of the coverage area Saturday into Saturday night.

Temperatures are still expected to warm, mainly due to increasing H7-
H5 heights late tonight through Saturday night, since full sunshine
on Saturday is not necessarily expected with the surface trough
slogging its way across MN/WI. That said, highs are still expected
to increase from the 60s area-wide today to the mid-60s to mid 70s
tomorrow. Lows both tonight and tomorrow night will generally run in
the mid 40s to lower 50s.

.LONG TERM...(Sunday through Friday)
Issued at 307 PM CDT Fri May 14 2021

Relatively benign weather returns for the start of next week, but a
more active pattern does appear to develop by the end of next week.

The period starts out with broad ridging taking hold over much of
the CONUS during the later half of the weekend, and persisting into
midweek. This will keep temperatures on the warmer end, with above
normal temperatures returning after a lengthy absence. Highs in the
upper 70s to low 80s look possible with overnight lows in the 50s to
near 60 towards the later half of the week. The forecast looks
mostly dry through midweek, with the main system of note being a low
that cuts off over the southwestern US. A few disturbances spinning
off of this feature could migrate into the area and bring some low
precipitation chances into southern Minnesota, but overall dry
weather is expected through at least Wednesday.

An amplified trough moves onshore the Pacific Coast midweek, and
ushers in more meridional flow into the region. This has the effect
of amplifying and tilting the ridge more over the eastern US,
allowing any disturbances shed off of the western trough to pass
over the region. Guidance remains in fairly good agreement with
depicting widespread precipitation chances Thursday into Friday, so
have kept PoPs in the likely range for the end of next week. The
meridional flow aloft will also allow for warmer and more humid Gulf
air to flow into the region, which will likely lead to at least a
few periods of thunderstorms. Anomalously high precipitable water
values also return to the region, which increases the possibility of
a soaking rainfall.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1251 PM CDT Fri May 14 2021

VFR to start at all terminals. KMPX radar shows scattered echoes
approaching and crossing I-35 but it is hit-or-miss as to whether
precipitation aloft is actually hitting ground. And if/where it is,
it is still within VFR range, so any TEMPOs which have precip have
maintained VFR conditions, just in lower ranges. Potentially,
additional precipitation is expected in western MN later this
afternoon with some heavier intensities than could drop visibility
into MVFR range. Otherwise, going into this evening, precipitation
chances drop off to a less-than-mentionable chance but not completely
ruled out so have kept things dry after 00z. Ceilings are expected to
drop as winds become lighter (but not altogether calm to promote
fog) and moisture is trapped under the nightly inversion so MVFR to
IFR ceilings can be expected overnight through daybreak Saturday.
Conditions will steadily improve to VFR. Winds this afternoon will be
breezy from the S and SW then speeds drop off tonight into tomorrow.

KMSP...VFR to start and very likely VFR through any precipitation
during the rest of this afternoon and early evening. Degraded
conditions look to start after this evening's push and remain in
place through the Saturday morning push, including ceilings below
1700ft. Not expecting IFR at MSP but that cannot be ruled out during
the hours around sunrise.

/OUTLOOK FOR KMSP/
Sun-Wed...VFR. Wind SE 5-10 kts.

&&

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

SHORT TERM...JPC
LONG TERM...ETA
AVIATION...JPC

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
300 PM CDT Fri May 14 2021

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
152000-
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns-
Benton-Sherburne-Isanti-Chisago-Lac Qui Parle-Swift-Chippewa-
Kandiyohi-Meeker-Wright-Hennepin-Anoka-Ramsey-Washington-
Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota-
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-Polk-Barron-Rusk-
St. Croix-Pierce-Dunn-Pepin-Eau Claire-
300 PM CDT Fri May 14 2021

This Hazardous Weather Outlook is for portions of central and
southern Minnesota, and west central Wisconsin.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
559 PM CDT Fri May 14 2021

MNZ054-142345-
Lac Qui Parle-
559 PM CDT Fri May 14 2021

...A STRONG THUNDERSTORM WILL AFFECT WEST CENTRAL LAC QUI PARLE
COUNTY...

At 559 PM CDT, a strong thunderstorm was located near Marietta, or 17
miles southeast of Milbank, moving east at 20 mph.

Winds in excess of 30 mph and dime size hail are possible with this
storm.

Locations impacted include...
Madison, Marietta, Cerro Gordo and Madison Airport.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 4500 9642 4511 9641 4510 9606 4492 9607
TIME...MOT...LOC 2259Z 273DEG 18KT 4505 9635

ETA