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fxus63 kmpx 131716 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1116 am CST Wed Nov 13 2019

Short term...(today through thursday)
issued at 353 am CST Wed Nov 13 2019

The forecast remains mainly on track regarding the light snow today,
with the only change being to delay the onset of snow by a few
hours this morning. The 00z sounding at mpx showed a sizable
amount of dry air below 600 mb, and hrrr/rap forecast soundings
show this layer slow to saturate this morning. Current obs show
light snow as far south as a Fergus Falls to Hayward, WI line, so
expect light snow to begin relatively soon across northern
portions of the County Warning Area and slowly spread south across central
Minnesota and northwest WI early this morning. Further south
towards the Twin Cities Metro and I-94 corridor in west-central
WI, snow is expected to hold off until mid to late morning, which
should lessen potential impacts to the morning commute. Snow will
be most widespread from the late morning through mid afternoon as
the mid-level frontogenesis generating this band of snow peaks
over the region, with snow tapering off from west to east during
through the late afternoon and evening. Snow amounts are expected
to be light as there is not much moisture for this system to work
with, especially given the very dry air to overcome. Expect most
locations to see accumulations around half an inch to an inch,
with 1 to 2 inches possible along and north of I-94 in west-
central Wisconsin.

Winds turn northwest behind this system, with another shot of
Canadian air resulting in a chilly morning Thursday, as
temperatures drop into the low to mid teens. Ridging begins to
nose into the ridging on Thursday, with skies clearing out during
the day and temperatures warming into the 30s.

Long term...(thursday night through tuesday)
issued at 353 am CST Wed Nov 13 2019

No significant weather impacts are expected during the long term
period, with temperatures expected to be back up near seasonal
normals by the weekend and into next week.

Models are in pretty good agreement on the large scale flow pattern
during the long term. We'll have zonal flow over the weekend as
the northern stream shifts north into Canada, with flow
transitioning to northwest next week. However, the ridge setting up
over the West Coast next week is much shallower than what we have
been experiencing, so it will not be tapping into Arctic air,
instead we'll be getting air coming down off the Canadian rockies,
which will allow for seasonable temperatures to continue, even in a
northwest flow regime.

For potential weather systems during the long term, there's one
common thread in all of them, a lack of moisture. The first boundary
we'll see comes Friday, when a backdoor cold front comes down from
another lobe of Arctic air that will be staying off to our northeast
this time around. There's no forcing or moisture for this front, so
it looks to do nothing more than provide US with stratus. Next up
comes Saturday night into Sunday when an elongated positively tilted
h5 through and associated front moves through. Moisture will be
better with this one, but forcing is pretty meager and mainly tied
to moisture convergence along the front. Still hit-and-miss in the
model realm as to whether we'll see any quantitative precipitation forecast with the front, so we
have kept the chance pops going, with p-type mainly snow during the
overnight hours, transitioning to rain during the day. Again, we're
not looking at any significant quantitative precipitation forecast values, so if we do see snow,
accumulations would be very minor.

Next week, we transition to northwest flow and that transition
begins Monday with a clipper system. The biggest impact this clipper
will have is that we'll be in the warm sector of it, so Monday looks
to be the warmest day of the next week, with some low 50s northeast
of the Buffalo Ridge not out of the question if we time things right
with the passage of the cold front. Beyond Monday, there's small
pops somewhere in our area every period, which is just the result of
being susceptible to seeing weak, fast moving waves in the northwest
flow. On the whole it looks to be dry, though cloudy next week. H85
temps will be within a couple degrees of 0c, so highs will be up
around 40, while the cloud cover should keep lows up above 30 for
the most part as we start to dig out of the temperature departure
hole we've dug after the first 12 days of the month (which is near
12 degrees below normal).


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1110 am CST Wed Nov 13 2019

Worst conditions of IFR vsby in -sn will occur between 18z and 22z
across southern Minnesota, and into west central Wisconsin. MVFR
cigs will linger in central Minnesota, but vsbys should be
unrestricted as the -sn will have ended. MVFR cigs will linger
across eastern Minnesota, and into west central Wisconsin into the
evening, with VFR conditions likely not until after 12z in parts
of west central Wisconsin. Winds will become northwest this
afternoon, and gusty in western/central Minnesota.


High confidence of IFR vsby in -sn until 20z, with vsby increasing
to MVFR/VFR between 20-22z. MVFR cigs will also continue through
the afternoon, and evening before VFR late tonight. Lower
confidence on cigs lower than 1.7 kft, but the best time will
occur along with the -sn this afternoon. Winds will become
northwest by 20z and increase to around 10 kts.

/Outlook for kmsp/

Thu PM...VFR. Wind west-southwest 10 kts.
Fri...VFR. Wind east 5-10 kts.
Sat...MVFR -rasn possible late. Wind S 10-20 kts.


Mpx watches/warnings/advisories...



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