Hurricane Helene continues to develop and approaches landfall, and models show rainfall potential reaching the Quad Cities later this week. This track from a tropical system hasn’t been seen for decades. Helene, which is forecasted to become a category 3 hurricane, will bring heavy rainfall to the Gulf Coast.
The cone projection, another word for a hurricane track, for Helene forecasts it all the way to the Illinois-Indiana border, forming a sort of banana hook from the Florida Gulf Coast to the Midwest. This means we could see some rainfall from Helene reaching us all the way here in the Quad Cities.
The last time a tropical system hooked from the Florida Coast to here in the Quad Cities dates back to almost 120 years ago before tropical systems even received names! “Unnamed Tropical Storm” 1906 made landfall near the Florida-Alabama border on June 12, 1906 and reached the Quad Cities area on June 14, 1906.
Helene’s potential track runs all the way to Illinois because of the Fujiwhara Effect.
The Fujiwhara Effect
The Fujiwhara Effect occurs when two areas of low pressure rotate around each other. Fujiwhara Effects are not very common, and typically occur over the open ocean or as one low pressure over the ocean meets with one on land.
For Hurricane Helene, it will be meeting with an area of low pressure that currently resides in Missouri that is an upper level low, a cyclone in the upper atmosphere that contains cold air. It will grab the low pressure that is Helene moving Northwest and bring some potential rainfall here to the Quad Cities.
The reason that Helene is meeting with this other area of low pressure comes from a Jet Stream riding down into Texas then moving North to Northern Alabama and Georgia. This jet stream will be the catapult for Helene being sent to the Midwest, bringing cloud cover and potential rainfall from Helene here to the Quad Cities.
The rainfall we could see from Helene as it hooks Northwest could come as early as Friday with our best chance of seeing showers coming on Saturday.
While those are the current forecasted time frames, predicting a situation like this can be very tricky. A lot of the showers we could see depends on which low absorbs the other in a sense. We could see little-to-no rain at all if the low over Missouri ends up as the “dominant” system. Most rainfall from Helene could remain South.
