Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
926 FXUS63 KDTX 142303 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 703 PM EDT Fri Jun 14 2024 .KEY MESSAGES... - Seasonable temperatures are expected again Saturday before heat begins to build late Sunday. - An extended period of hot weather will then set up next week with temperatures in the mid 90s to occasionally upper 90s and maximum heat indices near 100 degrees. && .AVIATION... Great Lakes modified high pressure builds farther into Lower MI tonight taking control of aviation weather with clear sky and light NE wind. High based cumulus fade with sunset this evening while lake breezes release and wash out in favor of light NE surface wind late tonight and in the morning. Clear sky is followed by a gradual cirrus increase while lake breeze enhanced easterly wind redevelops in the afternoon into Saturday evening. For DTW/D21 Convection...No thunderstorms are expected. DTW THRESHOLD PROBABILITIES... * None. && .PREV DISCUSSION... Issued at 345 PM EDT Fri Jun 14 2024 DISCUSSION... Upper level ridging over the central/southern plains translates east through the area this weekend and then expands to cover much of the eastern seaboard/northeast CONUS on into the deep south early next week with the western periphery of this upper system encompassing the eastern Great Lakes into lower Michigan. After another pleasant day on Saturday with high temperatures in the 70s to around 80 and relatively low humidity, this ridging will bring the beginning of an expanding area of heat Sunday with highs in the mid 80s to around 90. While the center of this upper ridge will be positioned off to the east and southeast, its magnitude/expansion will ensure it has a strong influence over the region as an increasingly hot airmass works into the Ohio Valley and Great Lakes. High temperatures will build into the mid 90s (and in some cases upper 90s) on Monday with humidity levels edging up to some degree as well. A similar prospect is in store for Tuesday as well. However, one potential complication in the forecast has developed as medium range models now bring an upper level wave northward around the western edge of this ridge into the area. This system will originate from the area of disturbed weather currently positioned from far south Florida into western Cuba. This will bring a chance of scattered, mainly afternoon, showers and thunderstorms with in on Tuesday. The additional cloud cover/moisture with this system may limit the high temperatures somewhat, but still expect most locations to exceed 90 degrees. In the wake of this upper wave, the upper ridge will re-orient such that the western lobe will pivot into the Ohio and Tennessee Valley regions as opposed to the deep south with the northwestern periphery of the system remaining solidly over the forecast area. This will lead to a continuation of hot weather through the mid to late week period. Model differences as to how much shortwave energy traverse the edge of this ridge begin to crop up by this time frame and this will have an impact on the extremity of eventual heat and also the potential for periodic scattered convection late in forecast period. As it stands, headlines for this period of hot weather will no doubt be needed for much of next week with the eventual degree/duration of heat determining the exact hazard. High temperatures in the mid 90s with heat indices of around 100 at times are consistent with Heat Advisory criteria, but the cumulative impacts from a more extended period of hot weather may very well warrant a Excessive Heat Warning in time. The degree of expansion of the ridge back into the area by the middle of next week will be the main player in this distinction. Also, one "relative" positive during this upcoming heat wave will be modest humidity levels. This lack of significant moisture will allow temperatures to edge back into the 70-75 degree range each night. MARINE... High pressure in control this weekend, bringing gentle winds across Lake Huron. Conditions hold through the weekend ahead of a warm front moving across the area Sunday evening. Southeasterly winds will veer southwesterly and strengthen to 10-15 knots. Chances for showers and storms exist with this event, mainly over northern Lake Huron. Winds are expected to remain gentle to moderate through the rest of the week along with chances for unorganized showers to move across the area. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....BT DISCUSSION...DG MARINE.......BC You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.