Dense Fog Advisory 13, NWS Twin Cities, MN

911 
WWUS73 KMPX 141756
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
1156 AM CST Tue Nov 14 2017


MNZ041>045-048>050-141900-
/O.EXP.KMPX.FG.Y.0013.000000T0000Z-171114T1800Z/
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Pope-Stearns-Benton-
Including the cities of Alexandria, Long Prairie, Little Falls, 
Princeton, Mora, Glenwood, St Cloud, and Foley
1156 AM CST Tue Nov 14 2017

...DENSE FOG ADVISORY WILL EXPIRE AT NOON CST TODAY...

Visibility has improved but may decrease again into the evening.


$$

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
610 AM CST Tue Nov 14 2017

.SHORT TERM...(Today and tonight)
Issued at 319 AM CST Tue Nov 14 2017

Areas of fog and drizzle are persisting across the region this
morning. The fog became dense in parts of west central MN
overnight which prompted a Dense Fog Advisory until 9 AM, but it
could be extended with guidance showing the fog continuing into
the afternoon. It may also be expanded eastward if near term
guidance is correct with visibilities dropping during the next few
hours. Radar indicates the best drizzle is currently occurring
from Mankato toward Eau Claire. This should taper off during the
predawn hours with patchy drizzle occurring through the day. The
better chance for drizzle or steadier rain will occur again this
evening ahead of the front when low level lift is maximized. Drier
air will follow the front tonight which should kick out the fog
and drizzle.

.LONG TERM...(Wednesday through Monday)
Issued at 319 AM CST Tue Nov 14 2017

As with the previous forecast, the extended period remains
uncertain in terms of timing, and how widespread the precipitation
develops Friday, and whether a much colder pattern develops next
week.

First, the upper air flow remains progressive and fast through
Friday. Differences remain in the GEM/EC/GFS on the speed of the
positive long wave trough moving across the Rockies and into the
Plains by Friday. The GFS continues to be the fastest with this
wave, and the GEM/EC have been the slowest. It is becoming apparent
that weather models have been difficult in determining the phasing
of the southern and northern jet streams entering the west coast
this week. Thus, the differences in each model run have play a
significant role in the timing and surface features later this week.
Several of the past model runs have tried phasing the jet streams,
but still have trouble, especially in terms of a split flow regime.
One item that is becoming apparent is the much warmer air flowing
northward before the main energy moves into the Plains. Therefore,
most of the precipitation will be in the form of rain. Only a brief
change over to snow is possible once this system departs to the east
sometime Friday night/Saturday morning. Due to the continued
problems with the models phasing the two jets, there is low
confidence on how widespread the precipitation becomes, and timing
could be a problem due to some of the energy further to the south.
The current forecast has decreased percentages to chance for most of
Minnesota, with western Wisconsin still having likely chances. I
would not be surprised to see these percentages decrease or even
increase once again as the system moves onshore and interacts with
the Rockies.

There is no doubt that once this system moves east of the Great
Lakes, a blast of Arctic air will move southward across the Upper
Midwest for the second half of the weekend.

Next week colder pattern remains questionable due to uncertainties
in the long wave pattern becoming established. Longer range
teleconnection of the NAO/PNA support a strong upper low forming in
southeast Canada, with an upper ridge building across the northern
Rockies, and the plains of central Canada. This support is do to the
a strong negative NAO developing, and allowing for a blocking type
of ridge over Greenland, and the North Atlantic. This would keep the
upper low in southeast Canada and the continued flow from the Arctic
region for most of the eastern 1/3 of the nation. Differences in the
deterministic models of the GEM/EC/GFS is where does the upper ridge
become established. Will the upper ridge be further to the east
allowing for more modified air across the Upper Midwest? or does the
upper ridge remain further to the west, supporting a much colder
pattern which is in line with the current GFS.

The current forecast is a blend of the models. Therefore, very low
confidence in the extended period past this weekend. Check back and
see how the forecast changes based on the mean flow developing.

&&

.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 610 AM CST Tue Nov 14 2017

LIFR/IFR conditions will persist until a cold front passes through
tonight. Some improvement in visibilities across central MN is
anticipated this afternoon before deteriorating again this
evening. Drizzle and light rain will become more widespread this
afternoon and evening across WI and eastern MN.

KMSP...The biggest concern are cigs lowering to 400 ft for a time
this morning. All guidance suggests it's a strong possibility and
there are some obs nearby that have fallen that low. Otherwise,
IFR conditions to persist until late tonight.

/OUTLOOK FOR KMSP/
Wed...Chc MVFR. Wind NW 15G20 kts.
Thu...VFR with MVFR/-RASN possible late. Wind SE 10 kts.
Fri...MVFR with Chance -RA. Wind W 7-10 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Dense Fog Advisory until 9 AM CST this morning for MNZ041>045-
     047>050.

&&

SHORT TERM...BORGHOFF
LONG TERM...JLT
AVIATION...BORGHOFF

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
316 AM CST Tue Nov 14 2017

MNZ054-056>070-073>078-082>085-091>093-WIZ024-026-028-150930-
Lac Qui Parle-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-
Pierce-Pepin-Eau Claire-
316 AM CST Tue Nov 14 2017

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

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.

MNZ041>045-047>053-055-WIZ014>016-023-025-027-150930-
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns-
Benton-Sherburne-Isanti-Chisago-Swift-Polk-Barron-Rusk-St. Croix-
Dunn-Chippewa-
316 AM CST Tue Nov 14 2017

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

.DAY ONE...Today and Tonight

Areas of fog and very low visibility will continue through mid
morning across portions of west central, central and east central
Minnesota, as well as west central Wisconsin.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.