Winter Weather in Ohio, February 5 to 6, 2025

Area Forecast Discussion
National Weather Service Northern Indiana
848 PM EST Wed Feb 5 2025

.KEY MESSAGES...

- Period of freezing rain/drizzle overnight with untreated
  surfaces likely to be very slippery.

- Another fast moving system may bring a wintry mix Saturday.

&&

.UPDATE...
Issued at 846 PM EST Wed Feb 5 2025

Radar trends are paltry, especially upstream over southern and
central Illinois; our source region for overnight
precipitation. However, episodic freezing rain and drizzle have
been reported at a number of locations in our forecast area
along the leading edge of a low-level trough and warm air
advection aloft. A 00z sounding from Valparaiso University depicts
a much improved low-level moisture profile these past 3 hours
in the vicinity of 850mb. Furthermore, dew points have been
steadily rising. This increases confidence (somewhat) that radar
returns will blossom over the next several hours.

The presence of drizzle, even upstream as reported by mPING
users, is leading me to stay the course at this time. Drizzle is
more efficient at ice accretion than rain because small
droplets are very efficient for accumulation. Furthermore,
stiff east/southeast wind will work to overcome latent heat
release and promote evaporational cooling. So, while radar is
not impressive this hour, drizzle can be just a problematic.

Lastly, forecast guidance still advertises a blossoming FZRA
shield across the IL-IN line these next several hours. This is
in response to our location in the left exit region of a 70-kt
500-mb jet moving into southern IL. A 50-kt jet is present at
850mb as well. The combination of improved low-level moisture
as depicted on observed soundings and the approaching jet(s)
ought to permit increasing coverage of FZRA these next several
hours.

&&

.DISCUSSION...
Issued at 250 PM EST Wed Feb 5 2025

Several challenges remain on the evolution of the approaching winter
event, with high confidence on most, if not all areas seeing a
period of freezing precip. Where confidence decreases is exact onset
of precip, mix of sleet across the north and lingering freezing
drizzle for the morning commute.

Freezing rain/drizzle that started back across Missouri this morning
was working northeast and attempting to expand in coverage across
IL, but is encountering a somewhat drier layer below 900 mb. Unlike
many of the past systems, column above 900 mb is already
generally saturated which should allow for onset of precip
within a few hours of the arrival of the deeper lift and
moisture. Temperatures have struggled to warm today, but should
make a run at freezing briefly across the south before falling
some this evening. Many models have trended towards a slower
onset of precip for the entire area with locations along the
US-30 corridor maybe not seeing anything until 2 or 3Z and even
later further north. In addition the warm nose may not penetrate
as far north as previously thought with 850 mb temps only 1 to 2
C and more shallow vs the deeper warm nose further south.
Despite these concerns, the only change to headlines was to slow
the start time north of US-30 to 10 PM based on the trends.
Once precip starts, we are looking at a 3 to 6 hour window of
accumulation of ice or possibly sleet across the north. Overall
accumulations will likely remain under a tenth of an inch, but
only a few hundredths is needed to make for difficult driving
conditions. Locations in the SE may see more of a convective
element that could allow for brief heavy rain that would limit
efficient accruing of the ice. The precipitation will wind down
quickly by morning, maybe ending at some drizzle (freezing?).
Slgt chc pops have been maintained through 12Z Thu to account
for this. Temps will warm Thursday above freezing, but it may
take much of the morning across the north for this to occur.

Few changes beyond tonight as yet another system arrives for
Saturday with a mix of precip expected once again. Warm nose may not
be as pronounced as the current system and confined mainly to SE
areas resulting in more of a snow/sleet/freezing rain setup with
frozen precip chances greatest across the north. Plenty of time to
sort out details on this system, but some minor travel issues could
arise. Struggle between high pressure to the north and additional
disturbances passing west to east into next week leaves lots of
uncertainty in the forecast.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 601 PM EST Wed Feb 5 2025

Existing TAFs were generally on track; only a few minor
adjustments to start and end times for FZRA. Dry air continues
to win-out in the short term, though dew points are rising
slightly and radar returns are on an upward trend. This has
resulted in a delay by one hour for the FZRA start at KFWA.
Duration of FZRA at KSBN is highly questionable based on some
guidance that offers a glancing blow. In contrast, the upper-
level trough, per water vapor, is beginning to amplify and lift
northeast which should result in an blossoming precipitation
shield.

FZRA perhaps ends sooner than advertised by an hour or two. Low
clouds scatter out very late in the afternoon with breezy
conditions.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Winter Weather Advisory until 10 AM EST Thursday for
     INZ005>009-104-204.
     Winter Weather Advisory until 10 AM EST /9 AM CST/ Thursday
     for INZ012>015-017-018-020-022>027-032>034-103-116-203-
     216.
OH...Winter Weather Advisory until 10 AM EST Thursday for OHZ001-
     002-004-005-015-016.
     Winter Weather Advisory until 10 AM EST Thursday for OHZ024-
     025.
MI...Winter Weather Advisory until 10 AM EST Thursday for
     MIZ078>081-177-277.
MARINE...Small Craft Advisory from 1 PM Thursday to 5 AM EST Friday for
     LMZ043-046.

&&

UPDATE...Brown
DISCUSSION...Fisher
AVIATION...Brown

Hazardous Weather Outlook...UPDATED
National Weather Service Northern Indiana
330 PM EST Wed Feb 5 2025

INZ005>009-104-204-MIZ078>081-177-277-OHZ001-002-004-005-015-016-
062030-
Elkhart-Lagrange-Steuben-Noble-De Kalb-Eastern St. Joseph IN-
Western St. Joseph IN-Cass MI-St. Joseph MI-Branch-Hillsdale-
Northern Berrien-Southern Berrien-Williams-Fulton OH-Defiance-Henry-
Paulding-Putnam-
330 PM EST Wed Feb 5 2025

...WINTER WEATHER ADVISORY NOW IN EFFECT FROM 10 PM THIS EVENING TO
10 AM EST THURSDAY...

This Hazardous Weather Outlook is for northern Indiana, southwest
Michigan and northwest Ohio.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

A wintry mix is possible for Saturday into Saturday night. A brief
period of lake effect snow is possible at its end later Saturday
night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

INZ012>015-017-018-020-022>027-032>034-103-116-203-216-OHZ024-025-
062030-
Starke-Pulaski-Marshall-Fulton IN-Whitley-Allen IN-White-Cass IN-
Miami-Wabash-Huntington-Wells-Adams-Grant-Blackford-Jay-
Northern La Porte-Northern Kosciusko-Southern La Porte-
Southern Kosciusko-Van Wert-Allen OH-
330 PM EST Wed Feb 5 2025 /230 PM CST Wed Feb 5 2025/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 7 PM EST  /6 PM
CST/ THIS EVENING TO 10 AM EST  /9 AM CST/ THURSDAY...

This Hazardous Weather Outlook is for northern Indiana and
northwest Ohio.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

A wintry mix is possible for Saturday into Saturday night. A brief
period of lake effect snow is possible at its end later Saturday
night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

LMZ043-046-062030-
New Buffalo MI to St Joseph MI-Michigan City IN to New Buffalo MI-
330 PM EST Wed Feb 5 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 1 PM THURSDAY TO 5 AM EST
FRIDAY...

This Hazardous Weather Outlook is for the nearshore waters of
southeastern Lake Michigan.

.DAY ONE...This afternoon and tonight.

No hazardous weather is expected.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Small Craft Advisory.