Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 231121

Area Forecast Discussion
National Weather Service Grand Rapids MI
721 AM EDT Sat Mar 23 2019


Issued at 140 AM EDT Sat Mar 23 2019

- Pleasant start to the weekend

- Showers arriving later Sunday ending as a brief wintry mix
  Sunday night

- Below normal temperatures early next week


.DISCUSSION...(Today through next Friday)
Issued at 140 AM EDT Sat Mar 23 2019

A big area of high pressure centered in Wisconsin will track
slowly southeastward through Lower Michigan today resulting in
tranquil weather. The combination of abundant sunshine and the
colder airmass shifting east will support higher temperatures than
Friday. Also...with a much weaker pressure gradient in place...the
winds will end up much lower today as compared to Friday. Overall
good drying conditions are expected.

It looks like the next storm system is tracking a little quicker.
Thus by Sunday afternoon there should be some rain showers moving
in. Despite thickening clouds we should still see temperatures
climbing to near normal or perhaps a few degrees above. It is
possible the temperatures will drop steadily mid to late afternoon
as the rain showers spread in.

A shallow colder airmass gets drawn into the storm system from the
north Sunday night. Forecast soundings do show a sub freezing
layer arriving around the time the precipitation will be winding
down. Therefore we could see a few slick spots showing up then. We
will maintain a risk for this to happen in the forecast.

The temperature at 925 mb is shown to tumble right through Monday
morning as a stronger north to northeast flow takes over on
backside of the strengthening storm. Well below normal surface
temperatures are expected which will continue right into Tuesday.
Pacific moisture is expected to spill over the mid level ridge
that tracks eastward through the region Tuesday into Wednesday so
there may be some clouds around. As heights will the
surface temperatures...especially Thursday. This is when the low
level jet arrives as well.

An unsettled pattern is shown to develop for the end of the week.
A digging mid level wave sets up to our west and slowly tracks
through the area. This system will tap Gulf moisture so the risk
for rain will increase. This pattern supports an increased risk
for heavy rain which will need to be monitored.


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 719 AM EDT Sat Mar 23 2019

With high pressure in control of our weather...the atmosphere will
remain relatively dry. This will act to limit the weather risks
to aviators. VFR conditions are forecasted along with winds that
will be under 15 knots most of the time.


Issued at 1218 PM EDT Fri Mar 22 2019

Rivers in the Grand and Muskegon River Basins remain high after rain
and snowmelt last week, but all sites have dropped below flood
stage. Standing water also continues to recede in Newaygo County,
however some roads there and in Kent County remain closed due to
high water. No flood warnings or advisories remain in effect.

River levels will continue to gradually fall through the next week
as only light precipitation occurs, and the snow that remains over
the Muskegon Basin undergoes a slow and steady melt as temperatures
warm back up.

The next chance for precipitation will be Sunday evening through
Monday morning. This should start as rain before mixing with and
changing to snow overnight. Total rain and melted snow equivalent
looks to remain below a tenth of an inch, and no impacts to river
levels or flooding are expected. A stronger low pressure system
looks to bring rain into the area again next weekend. Latest longer-
range models keep higher rain/snow amounts north of the forecast
area, but will keep an eye on trends as there is plenty of time for
significant track shifts.




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