textproduct: Detroit/Pontiac

KEY MESSAGES

- A Cold Weather Advisory remains in effect through Saturday morning with wind chill values between -15F and -25F. Actual low temperatures tonight expected to reach -10F to -15F for most areas.

- Long duration snow on Sunday into Sunday Night expected to produce snowfall in the 3-7 inch range for the Detroit Metro Area and locations toward the southern Michigan border, where the highest amounts are most likely. Lower snowfall amounts north of M-59.

- Cold/below normal temperatures continue next week.

DISCUSSION

Temperatures in the low single numbers this afternoon, though brisk westerly winds still are maintaining wind chills in the 15 to -25 F range across many spots. A Cold Weather Advisory remains in effect through 10 AM Saturday.

Afternoon surface dew pts in the negative teens to -20 F reveal the potential for very low temperatures tonight. Skies are expected to remain clear or mostly clear as winds attempt to decouple by sunrise. This occurs as a "bubble high" (eastward extension of the Arctic high over the upper Mississippi River Valley) develops over south Lower Michigan. Flint remains the best candidate to break its daily record low Saturday morning (see climate section).

Large upper level low off the Baja California coast will be kicked eastward, tracking through Mexico tomorrow. Southwest flow ahead of a highly positive-tilted northern stream trough tracking through the northern Plains will capture and merge with this southern wave. The 6hr 500 MB height fall center (~ -90 DAM) progged to track through central Ohio Sunday evening. Double-barrel lows, with the Mid Atlantic coast low deepening rapidly, will take over by Sunday night. However, the 12z Canadian/NAM both still indicating a substantial/closed low pressure center tracking northeast into the western PA/Pittsburgh area. This is typically a favorable track for Detroit Metro area to see deformation snow. Specific humidity in the 850-700 MB layer is expected to peak at 2 g/kg, reaching Monroe County Sunday afternoon, before tapering off to around 1.25 g/kg over Tri-Cities/northern Thumb region. Normally, with decent forcing, this would translate to 12-hour amounts of 1-4 inches. However, forecast soundings are indicating favorable lift and saturation in the DGZ (Dendritic Growth Zone) across a very deep layer (> 10kft), supporting high snow-to-liquid ratios in excess of 20:1.

As low-level winds turn northerly Sunday evening/night, some additional lake-effect contribution from Lake Huron is expected (although recent ice buildup over southern Lake Huron leads to some uncertainty), as 850 BM temps reside in the negative mid to upper teens. Based on this current set up, anticipating total snowfall amounts of 3-7 inches across the Detroit Metro Area and points south. The highest amounts are likely over Monroe county as 12z Euro shows 0.4 inches of qpf right at the southern Michigan border. Amounts will quickly taper off northwest of M-59, where initial dry air and weaker moisture advection/forcing results in little accumulation across Midland/Bay Counties.

The northern stream trough axis swings through the Central Great Lakes on Monday, with the next clipper system/re-enforcing shot of cold air (850 MB temps in the negative lower 20s) arrives on Tuesday. Outgoing NBM pops for snow showers seems too low, and could see the arctic front producing a dusting to 2 inch type flurry snow scenario.

MARINE

The Great Lakes will remain entrenched under an arctic airmass which will sustain strong overlake instability and thus steep mixing depths, allowing breezy conditions to continue through the day. Wind gusts around 25 knots are expected with decreasing trends into tomorrow morning as a strong high pressure system builds in. A Heavy Freezing Spray warning remains in effect until early tomorrow morning. A strong lake effect snow band/snow squall has set up across northern to north central Lake Huron aligned where low-level convergence is maximized. This snow band will sustain through tomorrow and will result in rapid reductions in visibility under the band. Widespread light snow to fill in over the southern Great Lakes on Sunday as an expansive low pressure system progresses across the southern US.

CLIMATE

The record low min temps for Saturday, January 24th.

Detroit: -13 Degrees (Set in 1963) Flint: -13 Degrees (Set in 1963) Saginaw: -13 Degrees (Set in 1963)

The record low max temps for Saturday, January 24th.

Detroit: 4 Degrees (Set in 1963) Flint: 5 Degrees (Set in 1963) Saginaw: 8 Degrees (Set in 1961)

PREV DISCUSSION

Issued at 131 PM EST Fri Jan 23 2026

AVIATION...

Dry air across the airspace is causing upstream lake effect cloud to scatter and lift as it reaches the local terminals. Pockets of low VFR ceilings will be possible through the afternoon, especially toward the west side of the airspace with tapering coverage to the east. Skies then clear tonight before high cloud begins to fill in ahead of the next low pressure system set to impact the Great Lakes this weekend.

For DTW...Pockets of broken 3.0 to 5.0 kft agl ceilings may survive to DTW from Lake Michigan, although dry air should help keep cigs above MVFR restrictions.

DTW THRESHOLD PROBABILITIES...

* Medium for ceilings aob 5000 feet this afternoon.

DTX WATCHES/WARNINGS/ADVISORIES

MI...Cold Weather Advisory until 10 AM EST Saturday for MIZ047>049- 053>055-060>063-068>070-075-076-082-083.

Lake Huron...Heavy Freezing Spray Warning until 5 AM EST Saturday for LHZ361>363- 462>464.

Lake St Clair...None. Michigan waters of Lake Erie...None.