textproduct: Detroit/Pontiac

KEY MESSAGES

- Coldest conditions of the week with exist today. A warming trend will then commence Wednesday and Thursday.

- A slow moving cold front will bring the next chance of rain late Wednesday night and Thursday. This frontal boundary will remain the focus for additional rainfall development Thursday night and Friday.

DTW THRESHOLD PROBABILITIES

* None

PREV DISCUSSION

Issued at 219 AM EDT Tue Apr 7 2026

DISCUSSION...

Higher magnitude cold held within deeper layer northwest flow along the backside of broad mid level troughing now entrenched locally early this morning. The ongoing cold air advective process contributing to some lingering pockets of stratus and the occasional flurry. A steady level of drying under improving column stability as high pressure encroaches will effectively scour out this moist layer going forward this morning, with the eastern thumb likely the slowest as some degree of moisture flux off lake Huron persists. Resident thermal profile will feature an 850 mb temperatures of -14 to -16c today, sufficient to maintain a surface temp at roughly 15 to 20 degrees below average. Highs mainly in the 30s. Any lingering early day gustiness fades with time as the surface high increases influence this afternoon. Dry and stable conditions tonight with plenty of open sky. Lows broadly distributed in the 20s.

Benign weather conditions Wednesday. Moderating thermal profile within the background of building large scale upper heights will offer a respectable uptick in daylight temperatures. Highs arriving near average for early April. Eastern extension of a warm front attendant to an organizing system across the northern plains will sweep through late in the day. Still little indication of anything more than some increase in cloud with this feature, as more meaningful moisture transport hangs well to the west. A more concerted period of warm air advection then emerges Wednesday night into Thursday. This will occur as greater height falls spread across the northern great lakes south of the parent low ejecting across Ontario. This will effectively draw the cold front into lower Michigan, offering an initial window for shower production as higher quality theta-e aligns with the southeast sagging boundary. Highest probability of precip centered 09z-18z early Thursday, before meaningful upward vertical motion at least temporarily fades along the frontal slope. Limited available instability given the unfavorable timing with generally light qpf offered by the collective ensemble - interquartile range from a few hundredths to less than quarter of an inch. Milder resident airmass Thursday affords highs back into the 60s.

Favorable underlying environment will exist for a secondary and potentially more meaningful period of rain to develop Thursday night and Friday. Mid level wave shearing along the southern flank of the broader mid level trough will initiate another period of deeper moisture transport /PW over 1 inch/ as 850 mb flow reaches upwards of 50 knots. This sets the stage for an increasing coverage of showers and possible embedded thunderstorms to emerge along the stalled frontal zone projected to linger in vicinity of southeast Michigan. Forecast continues to highlight a moderate probability for rain, with some uncertainty yet in exact frontal positioning. Ensemble guidance currently offers .3" for mean qpf and roughly .5" at the 75th percentile. Trailing height falls will finally shunt the frontal zone south by Friday night, with drier conditions returning for at least the first half of the weekend.

MARINE...

High pressure builds into the region today, leading to a drier day across the Great Lakes. Northwest flow holds through most of the daylight hours which keeps waves elevated enough for Small Craft Advisories. Winds then shift to the south-southeast tonight into Wednesday morning while the next low tracks toward Ontario. Broad pressure gradient tightening occurs as the low approaches late this week, with southerly flow increasing to 25-30 knots by Wednesday night. A strong 60-70 knot low level jet moves overhead Wednesday night as well, but stable conditions prevent much of that from mixing to the surface. Most areas will see gusts capped below 35 knots, with elevated wave heights being the main marine concern. The low will also slowly draw a cold front across the region late this week, resulting in several rounds of showers with potential for thunderstorms at times. High pressure then returns to start the weekend.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...Small Craft Advisory until 4 PM EDT this afternoon for LHZ441>443.

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