Area Forecast Discussion
Issued by NWS Grand Rapids, MI

Home | Current Version | Previous Version | Text Only | 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

000
FXUS63 KGRR 210532
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
132 AM EDT SAT MAY 21 2016

LATEST UPDATE...
Aviation

.SYNOPSIS...
Issued at 300 PM EDT Fri May 20 2016

A high pressure ridge will continue to dominate the weather
pattern and produce fair weather along with a continued moderating
trend of temperatures through the weekend into early next week.
The next chance for showers will come late Tuesday or Tuesday night
with a better chance for showers and perhaps some
thunderstorms beginning Wednesday.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 300 PM EDT Fri May 20 2016

Short term fcst concerns remain minimal. Decided to introduce
mention of a small chc of light rain showers over our far se fcst
area late tonight and Saturday based on a consensus of short range
computer model guidance trends the past 24 hrs.

A few light rain showers and sprinkles are already noted across
northern IN. A few light showers may clip our extreme sse fcst area
in the vicinity of a sfc trof and in pva as an upper level trough
moves through.

Otherwise fair wx will continue for the vast majority of our fcst
area tonight through the weekend as the high pressure ridge remains
in control of the wx pattern. High temps this weekend will reach the
lower to middle 70`s.

12z short range guidance consensus time height rh x sections
suggest a fair amount of high cloud cover will linger through
tonight and much of Saturday with more sun for Sunday.

.LONG TERM...(Monday through Friday)
Issued at 300 PM EDT Fri May 20 2016

Narrow upper ridge across the central Great Lakes on Sunday and
Monday begins to break down on Tuesday. Showers could move in as
early as Monday night, but the chances are low enough to leave out
of the forecast for now.

Coverage of storms should increase on Wednesday as sfc based
instability is expected to be sufficient. Strong moisture return
results in sfc dew points surging into the lower to mid 60s.

Showers and a few thunderstorms  linger through Friday as sfc
boundary becomes aligned with upper flow and stalls over or just
south of Lower Michigan with at least one wave moving along it. We
will carry chance POPs  along with slight chance for thunderstorms
Thursday and Friday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 132 AM EDT Sat May 21 2016

We are expecting that VFR conditions will prevail at all terminals
through 06z Sunday. We are seeing lots of mid cloud cover over the
terminals as of 05z, ranging from around 6k ft at KJXN, to 15k ft
at the I-96 terminals. This cloud cover will hang around through
the morning, before moving out. Some cumulus development will take
place this afternoon, with cigs around 5-6k ft if any cigs at all.
Skies will then clear around sunset, and winds will become light.

&&

.MARINE...
Issued at 300 PM EDT Fri May 20 2016

High pressure centered over the Great Lakes region will continue
to result in minimal wind and wave action with wave heights aob 2
ft through the weekend.


&&

.HYDROLOGY...
Issued at 1200 PM EDT Fri May 20 2016

The lone advisory that is out at this time is Maple Rapids. River
levels may fall low enough to cancel this by early Saturday morning,
if not by late tonight. There are no concerns at this time.

Dry air continues to dominate the overall weather pattern for now.
A shower or two may develop along the Indiana/Michigan border, but
should stay far enough south to keep our forecast area void of
rainfall. We then get into plenty more sunshine Saturday through
the daytime hours Monday. Chances for rain gradually increase late
Monday through the middle of next week. While conditions look
wetter and more active for that period, variability in the medium
range models make the extent of this moisture questionable. By
that time, rivers will have fallen and may have some room to
maneuver.

&&

.GRR Watches/Warnings/Advisories...
MI...None.
LM...None.
&&

$$

SYNOPSIS...Laurens
SHORT TERM...Laurens
LONG TERM...Ostuno
AVIATION...NJJ
HYDROLOGY...JAM
MARINE...Laurens



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