Weather Science

In the path: how Southern storms influence Rochester’s weather

Could it already be that time of year again? The end of August marks the return to school, retirement of beach towels and of course, the heart of the Atlantic hurricane season. That’s right, although the Atlantic hurricane season technically started on June 1st, early September is the activity peak. This season has been no different as Hurricane Isaac ripped into the Gulf of Mexico and made its presence felt from the Gulf of Mexico north into western and central New York.

For weather nerds like myself, the hurricane season brings anticipation comparable to Christmas, as any day during the humid summer months could mark the formation of a major hurricane.

As the summer has roared along, we have seen spectacular weather in the northeastern U.S. Strange huh? I guess meteorologists can breathe a big sigh of relief. We haven’t heard the public complain too much about “wrong forecasts” this summer, tough to mess up “Hot n’ Hazy”. But since we are in the brunt of hurricane season, there’s no telling when one of these storms will come our way.

National Weather Service graphic shows the path of Hurricane Irene, cite:

For instance, last August Hurricane Irene made its landfall on the Outer Banks of the Carolinas and proceeded to dump 15 inches of rain throughout parts of New England, causing flash flooding and fatalities. Wait, I thought hurricanes weren’t supposed to happen in the northeast, at least that’s what the weatherman said.. In the case of Irene, the storm followed the natural east to west movement in the tropics due to the easterly trade winds as it strengthened over warm ocean waters. However, as Irene progressed northward into our neck of the woods, the prevailing winds shift from easterly to predominately westerly, allowing for direct aim on the northeast.

National Weather Service graphic shows the path of Hurricane Isaac. Cite:

Hurricane Isaac followed this pattern into the Gulf, moving westward and making its long-awaited landfall just west of New Orleans. The Louisiana and Mississippi coasts took the brunt of Isaac due to their location in the northeastern quadrant of the hurricane. In any hurricane, it is common for extreme flooding in the northeastern quadrant of the storm due to its counter-clockwise rotation, pushing water on shore, resulting in serious flooding and storm surge. Isaac was also a slow mover, remaining nearly stationary for almost 3 days, exacerbating the flooding.

As Isaac progressed northward, weakening over land due to lack of moisture, (hurricanes need warm water to survive – it’s their fuel!) the mid-latitude westerly winds pushed moisture from Isaac to the northeast providing our region with crucial rain that helped alleviate our recent arid conditions. Let’s all face it, clear skies and 80 degrees everyday is pretty freakin sweet, but a little rain here and there is necessary. Besides, pretty sure the weatherman hit this one on the head, pretty sweet right?