Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
359 PM CDT Wed Jul 12 2017

.SHORT TERM...(This evening through Thursday)
Issued at 348 PM CDT Wed Jul 12 2017

By 4PM this afternoon, the frontal boundary had nearly pushed east
of Eau Claire County, with a northeast-southwest orientation. The
front will quickly depart to the east as will the chance for
thunderstorms. Coordination with the SPC lead to the decision to
keeping our eastern most counties out of the watch given the
timing and orientation of the front. There could be a few isolated
showers late this afternoon and into the evening in north central
MN, but expect those to dissolve near sunset.

As the upper trough to our north dips southward tonight, the large
stratus shield will advect in, bringing widespread low clouds to
the area by daybreak tomorrow morning. Meanwhile, the dew points
will be decreasing behind the front and with the cold air
advection (albeit delayed), highs tomorrow will be held in the low
to mid 70s under cloudy skies. Did not include any pops for
tomorrow, but I don't think it's out of the realm of possibility
to see a little drizzle from the low stratus.

.LONG TERM...(Thursday night through Wednesday)
Issued at 348 PM CDT Wed Jul 12 2017

A fairly repetitive pattern will be in place across the Midwest over
the next several days. Expect northwest flow to bring high pressure
across the region, with a few embedded Clipper-like shortwaves
brining a window of southerly flow, heat and moisture, and potential
for thunderstorms. This scenario replays itself a couple of times
late this week through next week.

Friday is shaping up to be absolutely gorgeous, with surface high
pressure centered over eastern MN, which means clear skies, light
winds, and tolerable dewpoints in the mid 50s. On Friday night the
surface high will shift east and southerly flow will develop on the
back side. This will bring increased temperatures and moisture over
the region, so by Saturday should see highs in the upper 80s to
lower 90s at most locations.

A weak shortwave is progged to move across Minnesota and Wisconsin.
MLCAPES of around 3000 J/kg will build ahead of and along a surface
trough associated with this wave. This will introduce a chance for
late afternoon and evening thunderstorms, but the better forcing
will be in the eastern half of the CWA.

This process repeats itself, with Sunday looking cooler and drier,
moisture rebounding on Monday, and then chances for thunderstorms
again late Monday and Tuesday. Severe weather is possible during
this time period with deep layer shear on the order of 40 to 50 kts,
and a couple to a few thousand J/kg of CAPE.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1247 PM CDT Wed Jul 12 2017

Upper level trough over far northern MN will sink southeastward
tonight and the widespread stratus across northern MN will advance
southward late tonight and spread across all TAF sites in our
area. Confidence is high in this happening, it's just a matter of
nailing down the exact timing. The other concern is how widespread
will IFR cigs be? Went for mostly low level MVFR cigs based on
several hi-res models, but could see more widespread IFR develop.
Winds have turned northwesterly for most already, except western
WI where they will soon turn as well. This afternoon will bring
10 knots with occasional gusts, and tomorrow will bring
northernly winds below 10 knots across the area.

KMSP...Still thinking the cigs hold off until ~3AM or 08Z and fall
below 017 during the morning hours. Don't see VFR conditions until
18Z or after.

/OUTLOOK FOR KMSP/
Thu...VFR. Wind NW 5-10 kts.
Fri...VFR. Wind variable less than 5 kts.
Sat...VFR. Wind SW 5-10 kts.

&&

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

SHORT TERM...SPD
LONG TERM...JRB
AVIATION...SPD

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
146 PM CDT Wed Jul 12 2017

MNZ070-076>078-083>085-091>093-WIZ024>028-131900-
Dakota-Le Sueur-Rice-Goodhue-Blue Earth-Waseca-Steele-Martin-
Faribault-Freeborn-Pierce-Dunn-Pepin-Chippewa-Eau Claire-
146 PM CDT Wed Jul 12 2017

This Hazardous Weather Outlook is for portions of east central
Minnesota...south central Minnesota...southeast Minnesota and
west central Wisconsin.

.DAY ONE...This Afternoon and Tonight

Very warm and humid conditions will create a situation where heat
illnesses may occur, primarily for those who are active outdoors
today.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Heat and humidity will build back into the region Saturday and
again early next week. People who are active outdoors will need
to remember to stay hydrated and take breaks as needed.

There is a chance of thunderstorms Saturday and Monday night
through Tuesday.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.

MNZ041>045-047>069-073>075-082-WIZ014>016-023-131900-
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-Redwood-Brown-
Nicollet-Watonwan-Polk-Barron-Rusk-St. Croix-
146 PM CDT Wed Jul 12 2017

This Hazardous Weather Outlook is for portions of central
Minnesota...east central Minnesota...south central Minnesota...
southwest Minnesota...west central Minnesota...northwest
Wisconsin and west central Wisconsin.

.DAY ONE...This Afternoon and Tonight

Very warm and humid conditions will create a situation where heat
illnesses may occur, primarily for those who are active outdoors
today.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Heat and humidity will build back into the region Saturday and
again early next week. People who are active outdoors will need
to remember to stay hydrated and take breaks as needed.

There is a chance of thunderstorms Saturday and Monday night
through Tuesday.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
105 PM CDT WED JUL 12 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0230 AM     TSTM WND DMG     2 SSW WYOMING           45.30N 93.01W
07/12/2017                   CHISAGO            MN   FIRE DEPT/RESCUE

            NUMEROUS LARGE TREES DOWN OAK AND PINE.
            POWER OUT MANY AREAS. BOATS FLIPPED AND
            DOCKS TWISTED ON AREA LAKES. COVERS
            TRI-COUNTY AREA. BETWEEN FOREST LAKE AND
            WYOMING.

&&

CARLYON

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
432 PM CDT WED JUL 12 2017

WIZ028-122200-
Eau Claire-
432 PM CDT WED JUL 12 2017

...A STRONG THUNDERSTORM WILL AFFECT EAST CENTRAL EAU CLAIRE
COUNTY...

At 432 PM CDT, a strong thunderstorm was located near Lake Eau Claire
County Park, or 21 miles east of Eau Claire, moving east at 25 mph.

Nickel size hail is possible with this storm.

Locations impacted include...
Lake Eau Claire County Park.

LAT...LON 4469 9092 4471 9111 4478 9112 4482 9092
TIME...MOT...LOC 2132Z 270DEG 20KT 4475 9104

AMK