Lansing, Michigan 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

664
FXUS63 KGRR 301134
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
634 AM EST Thu Jan 30 2025

.KEY MESSAGES...

- Rain/wintry mix tonight/Friday

- Chance of mixed rain/snow Sat night/Sunday

- Wintry mix possible mid week next week

&&

.DISCUSSION...
Issued at 326 AM EST Thu Jan 30 2025

- Rain/wintry mix tonight/Friday

Developing low pressure over north Texas will track toward the
lower Great Lakes today. Warm advection ahead of it will not only
push temperatures into the 40s across the cwa, rain will also move
into the cwa tonight. We`ll begin the day with some sunshine,
however, but see clouds advect northward ahead of the low during
the afternoon. There`s been a signal for several days that the
central cwa may see a brief 3-4 hr period around 12z of light
freezing rain...generally north of M-57 and south of US-10.
Surface temperatures in that area will cool overnight to around
freezing for a couple of hours and a brief glaze may develop. By
mid morning, though, surface temperatures will warm above freezing
ending the freezing rain threat.

Once the low moves east during the afternoon, some colder air will
advect south behind it and we`ll likely see the light rain mix
with some wet snow. Little, if any, accumulation is expected.

- Chance of mixed rain/snow Sat night/Sunday

Low pressure moving across the northern tier of states will
produce light precipitation in a warm advection/isentropic lift
environment. Much of the precipitation falling as light snow will
remain north of the cwa. However, there may be some light mixed
rain/snow along the trailing cold front, being aided by a decent
short wave moving across the state Sunday afternoon. Due to the
Pacific nature of this system, there isn`t much cold air with it
and highs will be in the lower to mid 40s Sunday.

- Wintry mix possible mid week next week

Models have divergent solutions regarding a mid week system and so
confidence on p-type isn`t very high at this point. The ECMWF
develops a low in the plains and tracks it toward central Lake
Michigan by Wednesday night. Whereas the GFS keeps the system much
farther south across the Tennessee Valley. A mix of the solutions
would put some rain/freezing rain across the southern cwa
Wednesday night and light snow to the north. We`ll continue to
monitor the evolution of this system.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 634 AM EST Thu Jan 30 2025

VFR conditions are expected through today. Low level winds shear
with the 850 mb jet is expected to develop this afternoon and then
shift east of the area this evening. MVFR to LIFR ceilings move
in slowly from the south tonight with most sites dropping below
1,000 feet by 6Z Friday. Rain/drizzle will move in late tonight,
with the better chances toward 12Z Friday. Low visibilities are
expected with the low ceilings and rain/drizzle.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 1 AM EST Friday for LMZ844>849.

&&

$$

DISCUSSION...04
AVIATION...RAH