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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
1210 am CST Tuesday Dec 1 2015

Short term...(this evening through Tuesday night)
issued at 325 PM CST Monday Nov 30 2015

Significant snow storm continues to rotate slowly northward
through the Central Plains on its way to the Great Lakes by early
Wednesday. The large upper low is still slowly making its way off
of The Rockies and into the middle-upper miss River Valley...allowing
for fairly widespread divergence aloft and broad scale lift. A
few isolated pockets of moderate/heavy snow this morning produced 1-3
inches of snow just east of the I-35 corridor all the way from the
Minnesota/Iowa border to St Paul. After a lull...the first main slug of
moisture pressed northward from Iowa into Minnesota and is currently in a large
swath over the weather forecast office mpx County warning forecast area along and S of the I-94 corridor. Have
seen reports of visibility down to 1/4sm-1/2sm in southwestern Minnesota with sites
closer to I-35 in the 1sm-2sm range once the snow commenced. In
some spots...the precipitation came as a mixture of -dz/-ip at the start
but once the deeper moisture and heavier rates took hold...the
precipitation changed over to -sn and that is how the rest of the event
looks to unfold. Radar mosaic shows the back edge of the first
swath of moisture shifting away from southwestern Minnesota and essentially
lining up along the I-35 corridor through central and west-central Minnesota.
This batch does contain some heavier bouts of -sn... and this will
last through late evening. Then there looks to be a several-hour-long
break in the precipitation per nmm/arw/hrrr/hopwrf forecasts and have tried
depict as such in the grids by dropping probability of precipitation to the chance range for
central- eastern parts of the County warning forecast area overnight into tmrw morning. The next
round of precipitation looks to be gathering impetus over eastern
Nebraska/western Iowa and this will slowly shift into the area during
the pre-dawn hours...making for another difficult commute Tuesday morning.
There is still plenty of moisture associated with this system as
quantitative precipitation forecast overnight through Tuesday is still in the 1/2 to 3/4 inch range. Snow
ratios will climb slowly tonight into tmrw... closer to 12 or 13
to 1...making additional snowfall tonight through tmrw very likely. The
highest snowfall will still be focused in southwestern Minnesota...but additional
snowfall amounts will range from 3-6 inches in western WI to 5-9
inches in western Minnesota...and these amounts are through the duration of
the event. Therefore...have opted to leave the current headlines
alone as they are delineated. As the system pulls away during the
day tmrw...there are some indications of drier blyr air being
wrapped into the system and this may allow for a p-type change to
-fzra/-fzdz at times tmrw evening and tmrw night before the
precipitation looks to largely come to an end by daybreak Wednesday
morning. The concerns are still there that this will be a heavy wet
snow...making for difficult travel conditions and difficult snow
removal. Owing to those concerns are that temperatures will not
change all that much from today into tonight and through tmrw. Highs in
the low-middle 30s will only drop to the upper 20s to lower 30s tonight
followed by highs again in the low-middle 30s on Tuesday.

Long term...(wednesday through monday)
issued at 325 PM CST Monday Nov 30 2015

Any lingering light snow is expected to continue to taper off by
Wednesday morning as the low pressure system moves eastward into
the Great Lakes region. Kept a slight chance of snow in our
eastern areas Wednesday morning...but after that dry conditions
are expected to prevail. Leaned toward the colder side of guidance
on Wednesday in our western fresh snow cover from the
storm earlier in the week will likely keep temperatures cooler
than expected. Seasonably cold conditions are expected through
Thursday...with highs in the low-middle 30s and lows in the teens.

Slightly milder and dry conditions are expected from Friday
through early next week as an upper level ridge builds over
central North America. A weak front could move through our area on
Saturday night...but with limited moisture and
precipitation is expected at this time. Highs in the upper 30s and
lows in the 20s are expected from Friday through the weekend.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1152 PM CST Monday Nov 30 2015

One last band of snow moving north through southern Minnesota extenind
just in to west central WI. This band will work through over the
next 2-3 hours and the concern after it moves through becomes
the chance for drizzle. IFR ceilings are likely to persist through
much of the period...however the hrrr is indicating that the middle
level dry slot that will push in early Tuesday morning could scour
some of the low level moisture and allow ceilings to lift or
temporarily scatter. Indicated some improvement at that time for
some of the sites...and will monitor upstream observations as the
dry slot approaches.

Kmsp...this second band of snow should be essentially done by 8-9z
with a better chance for drizzle behind it. Otherwise no change
from the main discussion.

/Outlook for kmsp/
Wednesday...VFR. Winds northwest around 10 kts.
Thursday...VFR. Winds SW 5-10 kts.
Friday...VFR. Winds S 5-10 kts.


Mpx watches/warnings/advisories...
WI...Winter Weather Advisory until midnight CST Tuesday night for

Minnesota...Winter Storm Warning until midnight CST Tuesday night for mnz047-

Winter Weather Advisory until midnight CST Tuesday night for



Short term...jpc
long term...additional

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