342
FXUS63 KGRR 291915
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
315 PM EDT Sun Mar 29 2026
.KEY MESSAGES...
- Showers and storms Monday night into Tuesday Morning
- Several rounds of storms possible Tuesday into Tuesday night
- Another chance for showers late in the week into Easter
&&
.DISCUSSION...
Issued at 300 PM EDT Sun Mar 29 2026
- Showers and storms Monday night into Tuesday Morning
Dry air today will give way to moisture advection tomorrow. The
zonal flow will shift late Monday into Tuesday. The forecast
remains fairly on track with a low level jet fueling storms
Monday night into Tuesday morning. The Upper level flow is fairly
zonal Monday night into Tuesday. However, there remains a ribbon
of moisture along with a short have trough that, coupled with the
LLJ, should allow for elevated convection overnight into Tuesday
morning. Latest soundings do show around 700 J/kg of CAPE. While
not huge, given the strong shear, that could prove to be ample
enough.
A strong cap remains in place so mixing down winds may prove
difficult. As such, large damaging hail remains the primary
concern. The timing is interesting as it could arrive around
sunrise, which could affect the morning commute. Latest Nadocast,
12Z Sunday, does indicate the potential for large hail through
Lower Michigan.
There is the potential for brief heavy rainfall with some of
these storms. While QPF shouldn`t be to high, this will be the
first of several rounds of potentially heavy downpours.
- Several rounds of storms possible Tuesday into Tuesday night
Depending on if storms from Tuesday morning linger or exit
quickly will set up the rest of the day. The above mentioned
trough will deepen and should bring several more rounds of
convection as that deepening trough treks through region bringing
another jet through the mid levels in the afternoon and evening
timeframe. Tuesday will see larger CAPE values in the afternoon
and a potential boundary through the southern lower Michigan.
Latest CAMS do show the potential for some low level shear along
the boundary so while tornadoes are not expected, can`t rule them
out at this time. Given the potential intensity expect the storms
to linger into the evening hours. Latest QPF has around an inch
through these systems. While heavy downpours are expected to bring
more rainfall, not expecting flooding at this time.
- Showers late in the week with colder air into Easter
The upcoming week is trending to be a more active pattern. Another
round of showers will be possible Thursday into Friday with
moist southerly flow. Friday should see a break in systems with
another system potentially streaming through over the weekend.
This could prove to be a wet Easter weekend. The solutions diverge
but a strong cold front potentially treks through Saturday night
into Sunday. Cold northwesterly flow will move in behind it with
850 temps potentially in the -7C range Sunday morning.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 124 PM EDT Sun Mar 29 2026
An expansive area of broken high clouds was noted on ir imagery
early this afternoon and those high clouds will remain through
much of the period. Low level flow will begin to strengthen from
the southwest aloft overnight resulting in some LLWS and then lower
cigs toward morning. VFR conditions are expected to remain in
place.
&&
.MARINE...
Issued at 300 PM EDT Sun Mar 29 2026
Small Craft Advisory has ended with a lull in winds and waves
until Monday night. Monday night winds will increase out ahead of
an approaching system. This will result in another chance for
Small Craft Advisory conditions Monday night into Wednesday.
Winds will shift from the southwest to the northwest behind the
front Tuesday before winds become more offshore Wednesday into
Thursday.
Thunderstorms are expected at times Monday night into Tuesday
night. Some could be strong to severe with large hail and
damaging winds the main threats.
&&
.FIRE WEATHER...
Issued at 1034 AM EDT Sun Mar 29 2026
Based on latest guidance the dewpoints should remain in the 20s
this afternoon. So have adjusted the Dewpoints down to reflect
that. This also will drop the RH`s into the upper 20s this
afternoon. So expecting a drier day today. Winds should remain
around 10 mph with gusts of 20 to 25 mph possible.
Temps should drop off between 6 PM and 8 PM and RH`s should
recover through that time to above 30 percent and increase as the
evening continues.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 5 PM EDT this afternoon for
LMZ846>849.
&&
$$
DISCUSSION...Ceru
AVIATION...04
MARINE...Ceru
FIRE WEATHER...Ceru
NWS GRR Office Area Forecast Discussion