textproduct: Detroit/Pontiac

KEY MESSAGES

- Frost and freeze headlines are in effect until 8 AM EDT.

- Below normal temperatures this afternoon with a renewed chance for patchy to widespread frost tomorrow morning.

- Dry weather and above normal temperatures next week.

DTW THRESHOLD PROBABILITIES

* None.

PREV DISCUSSION

Issued at 333 AM EDT Sat Oct 17 2026

DISCUSSION...

Efficient radiational cooling under mostly clear skies coupled with post-frontal northwest flow will allow temperatures to drop into the low to mid 30s across most of SE MI over the next 1-3 hours, with localized colder temperatures expected within the northern Tri- Cities. This will result in patchy to widespread frost development prior to daybreak. Frost and freeze headlines remain in effect until 8 AM EDT. Below normal temperatures hold this afternoon as highs peak in the low to mid 50s under mostly sunny skies. Another round of clear skies overnight will produce another cool morning as lows drop back into the low to mid 30s. Patchy to widespread frost will again be possible but a slight uptick in gradient flow may help keep temperatures a couple degrees warmer relative to this morning. Temperatures to then return to seasonal normals in the low 60s by tomorrow afternoon as flow will have backed to the southwest in response to high pressure building in through the Ohio Valley and Appalachia region.

High pressure under ridge amplification will then bring an extended period of dry weather and above normal temperatures for the remainder of the forecast period through the end of the week. This persistence forecast will see mostly sunny conditions and highs in the mid to upper 60s. Some readings in the low 70s will be possible towards the middle to end of the week once the ridge amplifies across the Midwest in response to a closed low that will travel south along the coastal Pacific, turning inland across southern California and opening up across the Four Corners region.

MARINE...

Gusty northerly wind quickly subsides through the morning as a ridge of high pressure translates across the central Great Lakes. As the center of the ridge settles into the Ohio Valley by this afternoon, wind direction backs to the west-southwest and helps usher in a milder, more stable air mass today. By Sunday morning, deep low pressure tracking into Hudson Bay will induce a tight pressure gradient and send a low-level jet across the northern lakes. Low- level stability will hold the bulk of the momentum aloft, but models offer some low end chances in gusts reaching 35 kt gales near the Straits and from outer Saginaw Bay into central Lake Huron. Elsewhere, gusts to 20 to 25 kt will be more common. These gusty conditions continue into Sunday evening before wind diminishes as the jet departs and high pressure builds northward into the Great Lakes. This brings about more tranquil marine conditions through early next week.

DTX WATCHES/WARNINGS/ADVISORIES

MI...Freeze Warning until 8 AM EDT this morning for MIZ047-048-053-054- 060>062.

Frost Advisory until 8 AM EDT this morning for MIZ049-055-063- 068>070-075-076-082-083.

Lake Huron...Small Craft Advisory until 10 PM EDT Sunday for LHZ421-422-441.

Small Craft Advisory until noon EDT today for LHZ442-443.

Lake St Clair...Small Craft Advisory until 10 AM EDT this morning for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory until 10 AM EDT this morning for LEZ444.