Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 260718

Area Forecast Discussion
National Weather Service Grand Rapids MI
318 AM EDT Sun Mar 26 2017

Synopsis/Short Term/Long Term/Marine

Issued at 317 AM EDT Sun Mar 26 2017

Rain will continue today and tonight as low pressure moves across
Lower Michigan. The rain will taper off Monday morning but then
another low approaches by MOnday afternoon with more wet weather.
High pressure and drier weather arrives on Tuesday.


.SHORT TERM...(Today through Tuesday)
Issued at 317 AM EDT Sun Mar 26 2017

Kept categorical POPs much of today as southerly fetch of deep
moisture continues along with isentropic ascent north of sfc warm
front. The front lifts north by afternoon with enough instability
to bring back the chance of thunder across the southern half of
the forecast area this afternoon.

Sfc low tracks across Lower Michigan and pulls away to the
northeast tonight with some drying out by Monday morning. This is
short lives as another low ejecting out of the base the longwave
western CONUS trough quickly follows for Monday afternoon and
night. The precip shield is progged to extend into the southern
half of the forecast area as the sfc center tracks just south of
Lower Michigan.

Northerly flow and drying/sfc ridging will arrive on the back side
of the low on Tuesday with showers ending by afternoon.

.LONG TERM...(Tuesday night through Saturday)
Issued at 317 AM EDT Sun Mar 26 2017

Fair wx will finally return Tuesday night through midweek as a
Canadian high pressure ridge to the north takes hold of our wx
pattern. Temperatures will return to near normal for this time of
year by midweek as well.

A bit more uncertainty now exists in terms of the fcst for late
in the week as the operational 00Z gfs guidance solution now
suggests that the ridge would remain in control of our wx pattern
through Thursday and Friday with the low pressure system emerging
out of the southern Plains states staying well south of our region
late in the week.

Conversely the 00Z ecmwf guidance still suggests that the low
pressure system will move much further north and bring our area rain
late in the week. This notion has been supported by a consensus of
most medium range guidance the past several days and the evolution
of the upper level pattern late in the week also favors this

Therefore we see the 00z gfs as an outlier solution and we will
maintain chc pops for rain late in the week. Temps should remain
rather close to normal for this time of year late in the week into
next weekend.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1145 PM EDT Sat Mar 25 2017

Primarily IFR conditions are forecast to continue overnight
through Sunday due to low cigs and reduced visbys in rain and
patchy fog. Brief reductions to LIFR are also possible due to very
low cigs. A few thunderstorms may develop during the early to mid
morning hours Sunday and again Sunday evening. Conditions should
remain primarily IFR through Sunday evening due to low cigs and
reduced visbys in rain and fog.


Issued at 317 AM EDT Sun Mar 26 2017

Winds will continue to gust to near 25 knots into this morning
then conditions should improve by this afternoon.


Issued at 307 PM EDT Sat Mar 25 2017

Locally over one inch of rain has fallen particularly over the
eastern reaches of the Grand River, as well as the Thornapple River,
Maple River, Looking Glass River, and Sycamore Creek. Additional
rainfall through Sunday will continue to aid in boosting river
levels for these areas. Above bankfull rises are anticipated over
the next few days for Ionia, Hastings, Maple Rapids, Eagle, and
Holt. Another round of rain toward the end of the week may ensure
that these rivers remain near or above bankfull. We will continue to
monitor the trends.


LM...Small Craft Advisory until 11 AM EDT this morning for LMZ844>849.



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