Area Forecast Discussion
Issued by NWS Duluth, MN
Issued by NWS Duluth, MN
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
098 FXUS63 KDLH 300520 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1220 AM CDT Sun Jun 30 2024 .KEY MESSAGES... - Quiet weather tonight through Sunday night. - More rain and thunderstorms are expected Monday through Tuesday. Locally heavy rain and isolated severe thunderstorms may be possible. - Rain and thunder chances persist at times through the end of the week (including Independence Day) and into next weekend. && .DISCUSSION... Issued at 405 PM CDT Sat Jun 29 2024 The radar is dotted with popcorn-style showers and even a little enhancement over the Bayfield Peninsula which is likely due to terrain/gravity wave forcing. This is all due to diurnal heating creating modest instability and cyclonic flow aloft giving it a synoptic boost. These showers are expected to persist until just after sunset and diminish pretty quickly after sunset as dry air filters in from the northwest. Tonight, expect skies to clear out and winds to become calm/light as high pressure approaches from the west. With dry air moving in, fog is not expected to be a concern tonight. There is the slightest chance that there could be some highly localized frost in the coldest of the cold spots (think inland in the Arrowhead). However, confidence is really low that temperatures will cool that much. We`re getting really late in the season, and even 10th percentile of models have temperatures as low as 38 except for maybe a spot or two in the tip of the Arrowhead that could approach 36. All-in-all, a chilly night with temperatures in the upper 30s to low 40s, but unless you live in the coldest of the cold spots, frost is not expected. Ridging builds over the Dakotas on Sunday with a surface high over the Northland. Expect plenty of sunshine, light winds, and seasonably mild highs in the low 70s. Southerly flow develops Sunday night, and from the west, a warm front with broad warm air advection out ahead of it and several weak upper-level waves will promote a broad area of rain. PWATs creep up to ~1.50", or ~90th percentile of climatology, so there will be some threat for heavy rainfall amounts. By and large, totals from a quarter to one inch are most likely across the region Monday through Tuesday, but some locally higher amounts reaching 2" or so can`t be ruled out. While flooding doesn`t looking likely at this time with a pretty transient setup expected, with locally heavy rain falling over well saturated soil, some localized minor flooding can`t be ruled out. There will also be potential for some thunderstorms Monday and Tuesday, most likely Monday afternoon/evening and perhaps again Tuesday afternoon/evening. Initial instability parameters don`t look too exciting as we look into severe potential. MUCAPE may reach up to 500-1000 J/kg and 0-6 km shear to 30 knots or so. Storms should also be elevated, so threats will likely be limited to some marginally severe hail and perhaps damaging winds on Monday. On Tuesday, there`s potential that the cold front may be passing through. Of course, timing is not perfect several days out, but a similar marginal severe threat may be possible Tuesday as well. Rain moves out Tuesday night, and Wednesday may be a largely quiet weather day with flow becoming more westerly. There may be some wraparound showers and perhaps storms, but severe weather isn`t expected. On Thursday (Independence Day), models are in decent agreement that another low pressure system may pass through and bring more rain and thunderstorms (at this point looking like a 50 to 60 percent chance). Details are still muddy that far out, but folks with holiday plans should keep a close eye on the forecast. Additional rain is possible Friday and into next weekend, but chances drop from about 50 percent on Friday to about 30 percent on Saturday. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1218 AM CDT Sun Jun 30 2024 VFR conditions throughout the forecast period. Winds will remain light and variable. High pressure will be over the region today with sunny skies expected. Some potential for very patchy fog and or low stratus, but odds are that this won`t affect TAF sites. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 405 PM CDT Sat Jun 29 2024 Winds will continue to decrease early this evening. Small Craft Advisories remain in effect until 01Z (8 PM CST) for most nearshore zones. Wind gusts to 25 knots remain possible until then, along with some wave heights to 4 feet along the South Shore. After that, winds become light from the northwest tonight, switching to southwest Sunday, then more variable Sunday night with quiet weather. East to southeast winds strengthen in speed on Monday with rain and thunderstorm chances increasing by Monday evening (50-70% chance). For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. MARINE...None. && $$ DISCUSSION...JDS AVIATION...Wolfe MARINE...JDS