Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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

000
FXUS63 KMPX 052125
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
325 PM CST Mon Dec 5 2016

.SHORT TERM...(This evening through Tuesday)
Issued at 325 PM CST Mon Dec 5 2016

An arc of rain and snow along the warm front stretching from near
Morris to St. Cloud and New Richmond will lift north late this
afternoon. Temperatures have been rising into the 40s south of
this precip and am expecting some milder air to lift across the
entire area early this evening. Meanwhile, the arctic cold front
will reach MN and eastern Nebraska around 00Z this evening. A band
of rain will develop in advance of it about the same time (near
the 21Z enhanced cloud tops on IR stretching from Sioux Falls to
MSP). This band will then head east with the cold front slowly
through the overnight hours. Max wet bulb temps aloft are above
0 deg C across eastern MN this evening, but the warmer air
retreats late this evening before reaching WI. So, p-type will
depend more on surface temperatures there. QPF of 0.10-0.15 inches
could mean about an inch of snow (more if forcing along the front
can spike up rates), but think rain will mix in until later
tonight. This kept forecast snow amounts below an inch except in
Barron and Rusk counties where elevation may help p-type stay more
snow. There, an inch or two will be possible through early Tuesday
morning.

Following the frontal passage, west southwest winds gusting to 35 to
45 mph are expected in a strong cold air advection regime.
Steepening low level lapse rates with the temperature profile
falling into the DGZ will facilitate scattered to numerous snow
shower development from mid morning through late afternoon. Snow
accumulations are likely in the region with the deepest DGZ and
moisture aloft, namely across central MN (north of a line from
Morris to St Cloud and Cambridge). An inch or two will likely fall
there. There will be some blowing snow if such accumulations
materialize. These snow showers could bring brief visibility
reductions to 1/2 mile. Snow shower coverage will diminish
heading south toward the IA border, closer to the system`s dry
slot.

.LONG TERM...(Tuesday night through Monday)
Issued at 325 PM CST Mon Dec 5 2016

The long wait of a "true" Minnesota winter will envelop the
region and will continue through the end of the extended period.
The long wave pattern will become controlled by a long wave trough
across northern North America with the center of the cold air mass
in central Canada. This type of flow regime will keep the Upper
Midwest cool, with bouts of colder than normal conditions for the
next two weeks in December. A strong west to east "zonal" flow
will commence across the CONUS which will lead to several short
waves moving across the region. This progressive pattern will make
it difficult for timing of precipitation events, especially due to
the warm air advection regime and how it becomes oriented along
the thermodynamic boundary.

Tonight`s and Tuesday weather system will slowly weaken, but
affect a large part of the Upper Midwest as it translates to the
east across the Great Lakes through Thursday. As it moves over the
Great Lakes, a surface trough will move southward across Minnesota
and western Wisconsin. As the moisture depth increases in the
dendrite zone and coincides with weak lift, expect scattered snow
showers late Wednesday night and into Thursday. This will be the
best chance of snow showers with only minor accumulations
expected. However, snow ratios will be much higher, roughly 15 to
25-1, which means any chance of measurable precipitation
associated with the snow showers could measure an inch or two of
light fluffy snow.

As mentioned before with the fast west to east flow, the next
system will likely affect the Upper Midwest Friday night/Saturday,
and possibly another late Saturday, and into Sunday. Current
models are fairly certain of accumulating snowfall this weekend,
but timing and moist depth remains in question. Chance percentages
will likely be altered based on location of the warm air advection
regime and moisture depth.

Temperatures during the extended period will range from lows in
the single digits to the teens, and highs in the teens and 20s.
This is good weather for snow making and for ice to form on area
lakes.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1253 PM CST Mon Dec 5 2016

The freezing fog has finally improved across western WI early this
afternoon but IFR cigs will continue for a while. A band of rain
(and snow possible over WI) will develop along the arctic front
late this afternoon and early evening, pushing across MSP/RNH/EAU
tonight. VFR conditions are generally expected ahead of the front
(with the exception of western WI) with MVFR conditions behind.
Scattered to numerous snow showers will develop Tuesday across
central MN and northwest WI with some light accumulations possible
and brief reductions in visibilities. Strong west southwest winds
with gusts to 35 kt also possible.

KMSP...Few sprinkles this afternoon, but the best chance of rain
will come with the front this evening. Snow showers will be most
numerous to the north Tuesday, but there is enough of a chance for
at least a prob30 at this point.

/OUTLOOK FOR KMSP/
Wed...MVFR. Wind WNW 15g25kts.
Thu...MVFR. Chc -SN. Wind WNW 15g25kts.
Fri...VFR. Wind NW 5-10 kts...becoming S.


&&

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

$$

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.