Area Forecast Discussion
Issued by NWS Gaylord, MI

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 44 45 46 47 48 49 50

FXUS63 KAPX 201037

Area Forecast Discussion
National Weather Service Gaylord MI
637 AM EDT Mon Mar 20 2017

.NEAR TERM...(Today)
Issued at 407 AM EDT Mon Mar 20 2017

High impact weather potential: None.

Pattern synopsis and forecast:

Zonal mid level flow across the central conus early this morning
with deep sfc low pressure over Hudson Bay, and a cold front draped
south through western Lake Superior, MN and IA. Warm advection and
upper divergence associated with a weak mid level shortwave trough
had produced rain and sleet showers, but these were departing NE
lower. There was even some thunder earlier across areas south and
west of Grand Traverse Bay, on the leading edge of steeper mid level
lapse rates. There was a secondary cold front extending west of the
deep sfc low, with a moisture starved atmosphere advecting south out
ahead of it into the border of Manitoba, Ontario and nrn ND/MN. The
better moisture was seen well north around the cyclonic circulation
of the sfc low itself.

The current showers/sleet will depart over the next couple of hours
while some disagreement on how much atmospheric moisture is left
behind in nrn Michigan. There is still going to be some decent lapse
rates above 750mb, but not as steep as what we saw overnight. The
hints of rain showers redeveloping on the cold front that crosses
later this morning and afternoon are still there. However, looking
at upstream observations and latest satellite, moisture appears to
be quite minimal for any good confidence in new showers. Will only
go with chance wording for primarily nrn lower.

Whatever possibly develops should be out of here by this evening,
with us waiting on the secondary cold front that arrives late
tonight. The deeper moisture that surrounds the main low pressure
circulation never gets here. Am not going to include any chances for
precipitation attm, but it is going to be worth watching, especially
across eastern upper toward daybreak.

Highs today ranging from the mid 40s north to a few lower 50s south.
Lows tonight 25 to 30 most areas, with a decent drop this evening in
clearer skies and lightest of winds.


.SHORT TERM...(Tonight through Wednesday)
Issued at 407 AM EDT Mon Mar 20 2017

...LES near TVC on Tuesday...

High Impact Weather Potential...Moderate impact at the amounts are
expected to be minor to light amounts.

The sfc min RH will be at or below 25% on Wednesday and Thursday.
While temperatures and winds won`t be out of criteria, there could
be some minor impacts for fire weather purposes.

Pattern Synopsis/Forecast...Secondary cold front pushes into E Upper
around 12z/Tue and cools things pretty quickly as the models have
the 850 mb temperatures into the -13c to -15c range in E Upper by
18z. Models disagree about the synoptic moisture with the 850-700 mb
RH varying from around 35% to 55% by 18z/Tue. However, the NW flow
will begin to produce snow/rain showers into E Upper and NW Lower by
the afternoon. Although the GFS/HiResARW solutions have the snow
into NW Lower before 18z. Models continue the LES through 00z/Wed.
After 00z, the 1000-850 mb winds begin to veer to the North and the
850-700 mb layer begins to dry out. The layer RH falls to 15% by
12z/Wed. So will stop the snow by 12z. For Wednesday and Wednesday
night, dry conditions as the high moves over the forecast area and
clears the skies.

Primary Forecast Concerns...Snow amounts should remain light as the
amount of time and moisture will be limited for any good dump of
snow on Tuesday.

.LONG TERM...(Wednesday night through Sunday)
Issued at 407 AM EDT Mon Mar 20 2017

High Impact Weather Potential...

High Impact Weather Potential...minimal.

Extended (Thursday through Sunday)...Thursday the return flow on the
back side of the sfc high begins to produce an increase in moisture
and warm advection ahead of the next system. Models are in much
better agreement with the precipitation starting sometime after
00z/Fri and spreading across the forecast area by 12z. The
precipitation type overnight looks to be snow as a system gets going
out on the C Plains. However, Friday morning it looks like the snow
will change to rain in the morning and remain rain through the day.
Friday night, the cold air will begin to force the warm front south
despite the warm advection. This will continue rain in N Lower for
most of the night, but mix and change to snow in E Upper by 06z. The
snow will probably get into N Lower between 06z and 12z, with the
rain remaining dominate along the M-55 corridor. Saturday, the warm
air moves north again and the snow changes to rain again. The GFS
clears out the rain by Sunday, while the ECMWF does it by Monday


.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 630 AM EDT Mon Mar 20 2017

A weak cold front will sweep across the area later this morning
and into the afternoon and may bring a period of MVFR cigs to
primarily PLN/APN. Still a small chance for light showers
redeveloping today with the front. Mostly light winds expected
through the period before a secondary stronger cold front nears
late tonight and mainly Tuesday with increasingly gusty NW winds.


Issued at 407 AM EDT Mon Mar 20 2017

Slightly stable conditions over the Great Lakes will keep speeds
under advisory levels, out ahead of a cold front that crosses today.
A secondary cold front arrives late tonight into Tuesday, with a
good chance for advisory level gusts in stronger cold advection,
spreading into the region through Tuesday and lingering through
Tuesday night. Maybe a few light showers today, and light snow
showers Tuesday/Tuesday night.




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