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Area forecast discussion...corrected 
National Weather Service Duluth Minnesota
1147 PM CST Tuesday Nov 24 2015

Short term...(this evening through wednesday)
issued at 357 PM CST Tuesday Nov 24 2015

Complicated weather coming in the next couple days. A surface low
now developing over eastern Wyoming is expected to move east across
South Dakota tonight and up across Minnesota and into northwest
Ontario on Wednesday before ejecting off to the northeast. Ahead of
this system we should have copious low level moisture streaming up
into the area from the Gulf states...expected to form lots of
stratus and drizzle late tonight through Wednesday. The lift is not
strong enough to produce a band of actual rain with little or no I expect nearly all drizzle with only patches of
heavier drizzle. Of concern with this event has been the temperature
profile...with the warm air advection bringing lots of warm air up
into the forecast area...but surface temperatures remaining chilly
and fluctuating around freezing for at least the first 3-6 hours of
the event. Thus...have drizzle and freezing drizzle across the
forecast area. Temperatures tonight the main concern...dipping to a
minimum just below freezing this evening before beginning a slow
rise that continues through Wednesday afternoon. Wednesday night
the cold front behind the system moves through the forecast
area...and gradually turns the precipitation over to snow...with
another period of freezing drizzle possible during the transition.
During this time range the frontogenesis with the front weakens
overnight and precipitation amounts through the entire period
generally light and while things will be somewhat messy do not
expect a significant event out of this. However...if the freezing
drizzle becomes more prominent tonight and early Wednesday than I
currently think will happen we may have to act with an advisory.

Long term...(wednesday night through tuesday)
issued at 357 PM CST Tuesday Nov 24 2015

Thursday morning the broad frontal zone will be located over far
northwestern Wisconsin and will continue advancing southeast during
the day. Lingering light snow or a rain/snow mix is expected during
the morning over northwest Wisconsin. A second surge of moisture
will advance from the southwest by late morning/afternoon resulting
in an intensification of the precipitation and a change to all
snow...except in far southeastern Sawyer and much of price counties
where a rain/snow mix will linger through late afternoon. By 00z
Friday...precipitation will have switched to all snow. Ptype may
become a challenge again after 00z Friday as model soundings
indicated a layer of dry air encroaching into the region as the
front departs. There are some timing differences in the arrival of
the dry air...but a potential exists to sublimate ice crystals in
the dry layer...resulting in a transition back to freezing drizzle
as precipitation ends. Confidence was not high enough in the timing
or likelihood of this evolution to include fzdz in the forecast at
this time.

Skies will gradually clear Thursday night and Friday morning over
much of the area...with the exception of the international border
area which will see more cloud cover due to a transient shortwave
passing through far northwest Ontario. Otherwise...dry conditions
are expected. A Few Lake effect snow showers are possible in Ashland
and Iron counties before 18z Friday...but the potential seems to be cloud layer moisture quickly departs early Friday morning.

Quasi-zonal flow will arrive over the Northland by Saturday morning
resulting in mostly clear to partly cloudy conditions through the
weekend...along with gradually warming temperatures. By Sunday
night...the Broad Cut-off low which had been anchored over the
Desert Southwest...will begin to advance east-northeast across the
plains. This system will set up our next chance for precipitation
Monday night through Wednesday morning. Temperatures will be
relatively warm for the period and a mix of rain and snow is favored
at this time...changing to all snow by Tuesday evening. The usual
cautions apply with that system and changes in the three-ts...
track/timing/type...along with intensity of precipitation are likely
by early next week. Stay tuned.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1143 PM CST Tuesday Nov 24 2015

Conditions were still VFR late this evening...but by 11z-14z
MVFR/IFR conditions will overspread the area as low pressure
moves through...creating areas of light fog and drizzle. Later
this afternoon and evening precipitation will gradually switch
from liquid to light snow.


Preliminary point temps/pops...
dlh 31 37 24 27 / 10 30 20 20
inl 31 34 14 22 / 20 30 20 10
brd 32 37 22 27 / 10 20 10 20
hyr 31 41 28 31 / 10 50 50 50
asx 28 41 27 33 / 10 40 40 40


Dlh watches/warnings/advisories...
Ls...Small Craft Advisory until 4 PM CST Wednesday for lsz140.



Short term...le
long term...huyck

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