Area Forecast Discussion
Issued by NWS Quad Cities, IA IL
Issued by NWS Quad Cities, IA IL
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364 FXUS63 KDVN 270838 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 338 AM CDT Fri Sep 27 2024 .KEY MESSAGES... - Gusty northeast winds are expected today, up around 30 mph at times through the afternoon. - Temperatures this weekend will be warm by late September standards and it will become more humid. - A return to cooler, more seasonable weather is forecast for the first few days of October behind a cold front. && .SHORT TERM /THROUGH SATURDAY/... Issued at 315 AM CDT Fri Sep 27 2024 Today: SPC mesoanalysis and GOES WV imagery showed a large cut- off upper low centered over the Lower Mississippi Valley near western Tennessee and northwest Arkansas. Hurricane Helene has been moving quickly to the north tonight, already into southeast Georgia. It has now weakened to a Category 1 after making landfall earlier tonight as a Category 4. The tropical low will phase with the cut-off mid-level low positioned slightly to the west. The surface low will gradually pivot from the southeast into Kentucky, increasing the surface pressure gradient across eastern Iowa and northwest Illinois. Expect increasing NE to NNE winds with gusts between 25 - 35 mph (highest east of the Mississippi River). The gusty winds and dry conditions will lead to an elevated fire weather threat in cured agricultural fields, which is slightly favored east of the Mississippi River due to higher winds. Tonight - Saturday: The majority of the rain associated with the transitioning tropical to post-tropical system is forecast to hold southeast of the area. However, continual moisture advection via ESE flow aloft may support a brief period of mainly light rain (20-40%) across the far east-central to southeast counties late tonight into Saturday morning. Any rainfall amounts would be light, if anything occurs at all. For temperatures, expect highs to range from the mid 70s to lower 80s today and Saturday, warmest in the west and coolest in the east. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 315 AM CDT Fri Sep 27 2024 A weakening post-tropical Helene will stay to our southeast over the weekend as ridging aloft builds into the Midwest. We can expect highs in the upper 70s to lower 80s for most of eastern Iowa and northwest Illinois for Sunday - Monday. Moisture will also increase for Sunday and Monday with dewpoints in the upper 50s to lower 60s. A cold front will move through the Midwest Monday into Tuesday AM, ushering in a more fall-like airmass. Highs in the 60s/lower 70s and lows in the 40s/50s are forecast for Tuesday and Wednesday, right on schedule as we turn the calendar to October! The extended period of abnormally dry conditions will continue through at least this upcoming Thursday with high pressure building in behind the early week cold front. The NBM is showing dry conditions through Friday, and the GEFS and EPS have very low probabilities for measurable rainfall through this same period (less than 20% for most locations). && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1250 AM CDT Fri Sep 27 2024 Gusty NE to NNE winds will develop Friday morning as the tropical system "Helene" shifts northwestward into the Ohio Valley. The strongest winds are expected at MLI and BRL with peak gusts of 25 to 30 kts possible. VFR will prevail through the period with no precipitation expected. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Uttech LONG TERM...Uttech AVIATION...Uttech