Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
642 AM CDT Sun Mar 24 2019

.UPDATE...
Issued at 625 AM CDT Sun Mar 24 2019

Updated to include 12z aviation discussion below.

&&

.SHORT TERM...(Today through Monday)
Issued at 340 AM CDT Sun Mar 24 2019

Surface analysis early this morning shows an organized low
pressure system centered over central KS while an elongated cold
front stretches from central Quebec province through the northern
Great Lakes and across the Dakotas. Aloft, a compact cutoff low
sits atop the central Plains low pressure system while a longwave
upper level low spins over Hudson Bay with pronounced northwest
flow on the western fringes of that large upper low.

The surface low pressure system over KS is progged to slide east
across MO and into the lower Appalachians today through Monday
afternoon. Meanwhile, its associated upper level low will open up
and become absorbed into the northwest flow aloft by the time it
reaches the Appalachians Monday. As this low shifts east, it is
already spreading scattered light rain showers over southern MN
into southwestern WI this morning. Additional light rain showers
can be expected through the first half of the day south of the
Interstate 94 corridor but little to no measurable QPF is
expected. While this low shifts east, the cold front to the north
will gradually drop south this morning, moving south of MN/WI by
early this afternoon. This front will help shunt the precipitation
away from the area while no precipitation is expected from the
front itself. Actually, the main impacts from the frontal passage
will be a bit of cold air advection over the next 24-36 hours
along with a decrease in cloud cover tonight through tomorrow.

While highs today reach the lower 40s to lower 50s, the highest
of which will be in the southern half of the WFO MPX coverage
area, highs on Monday will only run in the upper 30s to lower 40s.

.LONG TERM...(Monday night through Saturday)
Issued at 340 AM CDT Sun Mar 24 2019

Still seeing warm signal around midweek with cooler conditions
early and again late in the period.

Retreating high pressure over the Great Lakes region should result
in a pleasant day Tuesday. We will see some mid/high level clouds
encroach the area from west during the day. Overall, should be
able to warm readings close to normal most areas.

Later Tuesday night and Wednesday we see increase southerly flow
in response to strong warming out ahead a developing frontal over
the Dakotas and eventual cyclogenesis to the southwest into
Thursday. Expecting to see southerly winds with guts to 35 mph
likely into southern Minnesota Wednesday afternoon. This will help
transport higher dewpoint air into the region with readings
around 50F expected. This should help erode most of the remainder
of the snow cover across about the southern half of the state.
Models showing very warm signal with Wednesday highs expected to
warm to the 60 to 65 range over much of the area. Clouds will be
the only limiting factor.

Instability is progged to increase with the GFS continuing to show
some MUCAPE values over 1000 j/kg into the region Wednesday night
along the frontal boundary. It remains the most bullish on
destabilization with the ECMWF building less instability into the
southwest. It is much faster with the front as well. 00z GEFS
plumes continued to show a high probability of at least 500 j/kg
into the region Wednesday night and tapering east into Thursday.
We will continue to trend more with blended guidance/GFS for now
and will continue with the slight chance of thunder with the
front. It should move into central MN by Thursday morning, exiting
to the east by Thursday evening.

Much cooler air filters in behind this front with flow over the
Great Lakes becoming more northwest aloft. Some trough energy does
move east over the western CONUS and drives a cutoff circulation
over Iowa/southern MN Friday/Saturday period. The ECMWF is farther
south with this feature as it has better northwest flow
established across the state by then. Still may see the far
southeast area of the CWA affected by this system and is would be
a rain changing to snow scenario Friday night into Saturday. We
retain chance PoPs at this time. Temperatures will cool to
slightly below normal into next weekend.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 625 AM CDT Sun Mar 24 2019

Little bit of a tricky ceiling forecast today due to two features
impacting the area. First, a low pressure system sliding east from
the central Plains into the mid-Mississippi River Valley. Second,
a cold front dropping south from central Canada. To start, patchy
fog in advance of the front is impacting western MN TAFs with
splotchy MVFR visibilities. Any fog is expected to burn off
shortly after sunrise but ceilings will gradually drop as well.
MVFR ceilings are most likely in western and central MN with the
cold front and the proximity of the passing low. Chances for MVFR
ceilings are less in eastern MN through western WI but confidence
not high enough to include it at this point and LAMP guidance has
a very small window of it occurring (2-3 hours this afternoon).
Will leave it out and see how the scenario evolves. Conditions
return to VFR this evening through tonight. No precipitation
expected.

KMSP...The main issue is the timing of any potential MVFR
ceilings. While chances remain low for MVFR ceilings at MSP, they
are non-zero. Best timing would look to be 20z-00z this afternoon.
However, will run with a solid VFR TAF at this point and see how
things develop today.

/OUTLOOK FOR KMSP/
Tue...VFR. Wind S 10-15 kts.
Wed...VFR. Chc MVFR cigs late. Wind S 15-20G30 kts.
Thu...MVFR likely. -RA likely with TS possible. Wind SW 5-10 kts
becoming NW.

&&

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

UPDATE...JPC
SHORT TERM...JPC
LONG TERM...DWE
AVIATION...JPC

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
301 AM CDT Sun Mar 24 2019

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
250900-
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-
301 AM CDT Sun Mar 24 2019

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

.DAY ONE...Today and Tonight

Flooding continues along the Mississippi, Minnesota, Crow,
Redwood, Sauk, Cottonwood, and Cannon Rivers. Flooding of smaller
creeks and streams, along with ponding of water over roads,
remains possible.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

The flooding threat on area rivers will continue into next week
due to snow melt and ice jam potential.

There is a slight chance of thunderstorms Wednesday night into
Thursday across parts of central and southern Minnesota.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed through tonight.

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
748 AM CDT SUN MAR 24 2019

MNZ041-047-048-241415-
Stevens-Pope-Douglas-
748 AM CDT SUN MAR 24 2019

...Patchy Dense Fog Expected through 9 AM...

Patchy dense fog, with visibilities of a quarter mile or less, will
impact the area through around 9 AM. If traveling, slow down and be
sure to have your headlights on this morning.

LAT...LON 4576 9625 4576 9576 4611 9577 4611 9514
      4577 9537 4542 9574 4542 9625
TIME...MOT...LOC 1247Z 180DEG 0KT 4564 9604