020 FXUS63 KGRR 141055 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 655 AM EDT Tue Jul 14 2026 .KEY MESSAGES... - Hot Temperatures Continue - Cooler Temperatures and Rain Chances Return Friday into Weekend && .DISCUSSION... Issued at 214 AM EDT Tue Jul 14 2026 - Hot Temperatures Continue A Heat Advisory is in effect for the entire area today with heat index values expected to be in low low 100s. This is due to the dome of heat in place under a strong high pressure system. 925 mb temperatures rise into the 26 to 29 C range and based on sounding profiles we expect high temperatures to be around 95 to 100 degrees with the highest values toward the US-127 corridor. Wednesday heights begin to decrease with the trough building over the eastern CONUS and us moving into more northwesterly flow between the ridge and trough axis. This will bring slightly lower temperatures to some areas, but with 925mb temperatures still in the 26 to 29 C range it won`t be much. We`ll still see highs in the 95 to 100 degree range and heat index values in the low hundreds. The best chances on the HREF are along and south of I-96. We`ll continue to monitor trends for tomorrow and consider where additional Heat Advisory headlines will be needed. Thursday will be a little cooler with highs in the upper 80s to mid 90s. Heat index values may approach 100 along the I-94 corridor. At this time any rain chances look to hold off until late Thursday night. - Cooler Temperatures and Rain Chances Return Friday into Weekend Northwest flow sets up for the latter half of the week with us nestled in between the ridge axis to the west and trough axis to the east. In this set up we`ll see shortwave troughs move quickly through the area and bring us several chances for rain and thunderstorms. Timing for each shortwave varies this far out, but the best chances look to be on Saturday when we see a more defined shortwave move through with a weak low level jet. Overall do not expect any one day to be a complete washout with more dry time than not Friday and through the weekend. Temperatures in this setup will not be as hot. Highs are expected to be in the 80s (some low 90s on Friday), with lows in the 60s. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 655 AM EDT Tue Jul 14 2026 No changes from the previous discussion. VFR conditions continue with southwest to west winds of 5 to 15 knots. A brief period of low level wind shear is possible between 6-9Z Wednesday with winds 25 to 30 knots around 2000 feet. && .MARINE... Issued at 214 AM EDT Tue Jul 14 2026 High pressure continues today with light westerly winds and waves 0 to 2 feet. Northwest winds develop tonight increasing waves up to 3 feet mainly north of Muskegon until Wednesday morning. Winds become more northerly toward the end of the week with chances for thunderstorms returning Friday through the weekend. Winds pick up over the weekend as well with the potential for Small Craft Advisory Conditions along with a moderate to high swim risk. && .CLIMATE... Issued at 214 AM EDT Tue Jul 14 2026 Here are the high temperature records for July 14 and 15. Location July 14 July 15 Grand Rapids 102 (1936) 95 (2013) Lansing 101 (1936) 99 (1977) Muskegon 94 (1995) 93 (1995) Kalamazoo 108 (1936) 103 (1936) Battle Creek 104 (1936) 100 (1977) Holland 98 (1995) 98 (1932) && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Heat Advisory from noon today to 8 PM EDT this evening for MIZ037>040-043>046-050>052-056>059-064>067-071>074. MARINE...None. && $$ DISCUSSION...RAH AVIATION...RAH MARINE...RAH CLIMATE...RAH

NWS GRR Office Area Forecast Discussion