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000 
FXUS63 KAPX 180741
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
241 AM EST Mon Nov 18 2019

.NEAR TERM...(Today through Tonight)
Issued at 238 AM EST Mon Nov 18 2019

Impactful weather: Minimal.   

Pattern synopsis and forecast: 

A mid level trough and sfc weak cold front was slowly working into 
the western Great Lakes, and was associated with a corridor of deep 
moisture that was also working through nrn Michigan. Very light rain 
and snow/flurries were embedded in this deeper moisture, as the 
forcing was pretty darn weak. Behind this front, colder low level 
air was seen from Lake Michigan back into Wisconsin, with deep low 
level moisture leading to solid overcast conditions, with areas of 
fog and potential drizzle/freezing drizzle. Very grungy.

The mid level trough axis and sfc cold front is expected to continue 
to slowly work into nrn Michigan today and hold through tonight. The 
very light rain and snow/flurries will continue into the morning, 
while the deeper low level moisture/clouds gradually overspread our 
neck of the woods. Fcst soundings suggest the moisture strips out 
aloft through the day, with the depth of the low level moisture not 
exactly getting up to -10C, suggesting mainly chances for drizzle 
for today, which may turn to freezing drizzle tonight as 
temperatures drop just below 32F. Chances for seeing any light 
precipitation will be greatest into western Chip/Mack counties of 
eastern upper, where data suggests there is just enough of a lake 
contribution to show a band working up the long axis of Lake 
Michigan. Also, chances will be higher in the higher terrain of 
interior nrn lower, where gentle upslope flow could increase lift. 
All-in-all however, whatever falls will be negligible and of minimal 
impact. 

Highs today will be in the mid and upper 30s, with lows tonight in 
the upper half of the 20s and lower 30s.

&&

.SHORT TERM...(Tuesday through Wednesday)
Issued at 238 AM EST Mon Nov 18 2019

High Impact Weather Potential: Patchy freezing drizzle possible 
across parts of the area Tuesday morning, perhaps leading to some 
slick spots on area roadways.

Pattern synopsis/forecast: Well-advertised weak/messy low pressure 
centered to our northwest by early Tuesday morning is expected to 
continue to plague the region with lots of clouds and some light 
mixed precipitation at times through Tuesday. However, by Tuesday 
night through Wednesday, return flow/warm air advection is expected 
to ramp up ahead of the next system set to eject lee of the Rockies 
midweek before trekking northeastward toward the Great Lakes late 
Wednesday night through Thursday.

Primary forecast concerns/challenges: Drizzle/freezing drizzle/light 
snow chances Tuesday.

By early Tuesday morning low pressure is expected to be sagging into 
the northern Great Lakes region while the system's center sits well 
off to our northwest across the Manitoba/Ontario border. Embedded 
shortwave troughing in larger scale parent troughing across the 
eastern third of the CONUS is expected to trek across northern 
Michigan through the day. As a result, some light/scattered bouts of 
mixed precipitation is expected to be the rule at times through the 
day. 

While model soundings suggest that the primary precipitation type 
will be drizzle and/or freezing drizzle depending on sfc temps (as a 
result of low-level moisture struggling to reach the -10C isotherm), 
there are certainly hints that periods of ice in the cloud are 
certainly possible, ultimately resulting in some mixed light snow at 
times. Given sfc temperatures progged at or below freezing across 
interior sections of northern lower and eastern upper early through 
mid Tuesday morning, those are the most susceptible locations to 
patchy freezing drizzle and perhaps some slick spots on area 
roadways. Lesser threat for this as you head near the coasts given 
sfc temperatures progged to be at or a couple of degrees above 
freezing, but certainly worth monitoring trends over the next 24 
hours for a potentially slower than desired Tuesday morning commute 
for some. Temperatures likely warm above freezing for the entire 
forecast area by midday, allowing any lingering patchy fzdz to 
transition to just drizzle. 

By late Tuesday night into Wednesday, low level return flow and 
associated low-mid level warm air advection are expected to ramp up 
locally as a result of low pressure intensifying to our southwest 
across the central plains. While sensible weather conditions are 
expected to be rather quiet through this time frame of the forecast, 
attention transitions to the late Wednesday night through Thursday 
night time frame in the long-term section below for what could be a 
a wet/windy storm system eventually transitioning to a bit of wintry 
precipitation.

Tuesday's high temperatures expected to range from the mid 30s 
inland to the upper 30s to near 40 degrees as you head near the 
coasts. Tack on a couple more degrees for Wednesday's highs... 
ranging from the upper 30s inland to the low 40s elsewhere.

&&

.LONG TERM...(Wednesday night through Sunday)
Issued at 238 AM EST Mon Nov 18 2019

High impact weather potential: Perhaps a period of mainly light lake 
effect snow Thursday night/Friday.

Focus through the long-term forecast period revolves around low 
pressure expected to surge from the midsection of the nation toward 
the Great Lakes Wednesday night through Thursday. Initial trends 
suggest northern Michigan lies firmly within the warm sector for the 
majority of the event, ultimately resulting in periods of rain 
across the forecast area as early as late Wednesday night across the 
western half of the forecast area before spreading eastward and 
continuing across the remainder of the area during the day Thursday 
(could be a few inland/higher terrain areas that remain near 
freezing early Thursday for a brief window of freezing rain at 
onset?). There do, however, remain a couple of individual ensemble 
members that attempt to slide the area of low pressure further 
south, which would spell a more wintry solution locally, but think 
that is fairly unlikely at this point. 

As low pressure quickly departs off to the northeast Thursday night, 
cooler air drops into the region behind the system...perhaps 
marginally cold enough to active lake processes once again and bring 
mainly light lake effect snow showers to some areas downwind of Lake 
Michigan & Superior through Friday. In addition, winds will be on 
the increase through the duration of this system with potentially 
some pretty gusty northwest winds/gales on the Great Lakes as the 
system treks to the northeast Thursday night through Friday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1148 PM EST Sun Nov 17 2019

A weak area of low pressure is over Ontario with a front 
extending down through the Midwest. Several pockets of light 
precip extend from the Midwest up through Lower Michigan and will
continue to move through the region overnight. Current VFR
conditions will deteriorate to MVFR/IFR as lower upstream cloud
cover slowly overspreads the region. 

Front will slowly cross the region through Monday/Monday night,
possibly stall. Light snow/rain-snow mix tonight will transition
to generally drizzle/low clouds and some fog/mist on Monday as 
temperatures climb to a few degrees above freezing.


&&

.MARINE...
Issued at 238 AM EST Mon Nov 18 2019

A weak pressure gradient is expected to keep wind speeds below 
advisory levels through at least Wednesday. Pretty uneventful as far 
as weather, with just some periodic light rain/drizzle in grungy 
conditions over this time. A better chance for rain arrives by 
Thursday, and possibly some stronger winds. 

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

$$

NEAR TERM...SMD

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