ITHACA, N.Y. — The last time I referred to an autumn heat wave as “Hot-tober”, my editor at the time, Jolene Almendarez (now in radio with Cincinnati NPR affiliate WVXU), sent me a well-meaning text with, and I quote, “Really Brian? That title is awful. Never again.”
Not that I want to risk my old editor’s wrath years later, but if I were to use that pun again, now would be a good time. Temperatures will be at or above 70°F for the week ahead, 10-15°F above normal, as a persistent jet stream ridge enhanced by an area of high pressure continues to pump warm air into the Great Lakes region over the next several days. Expect generally dry conditions until next weekend at least.
Your Weekly Weather
At present, a trio of synoptic-scale weather systems are impacting Ithaca and Tompkins County. To the south, a non-tropical area of low pressure off the Outer Banks of North Carolina, generating stormy weather and strong winds to the south; to the west, a warm front associated with a low pressure system over the Upper Midwest and lifting northwestward into Canada; and to the northeast, an area of high pressure over Atlantic Canada.
This makes for an interesting pattern in terms of advection, where the atmosphere aloft is being brought in from. The low on the Carolinas, rotating counterclockwise, is bringing warmer air poleward in its eastern flank, which is then picked up by the Atlantic Canada high’s clockwise circulation and brought poleward on the high’s western flank – which is over Upstate New York. The low to the west, also having a counterclockwise rotation as all Northern Hemisphere lows do, is bringing warmer air poleward on its eastern flank, which lines up with the high’s western flank. So in short, you have multiple avenues to bring warmer air into the Southern Tier, albeit with some instability from the lows, hence the cloudy skies.
For the rest of your Sunday, expect fairly mild and pleasantly dry conditions. The cloudy skies should develop a few more breaks as we head into the evening hours, with highs near 70°F , possibly above 70°F if the clouds break up a little sooner. Overnight tonight expect partly to mostly cloudy skies with overnight lows in the mid to upper 50s, rather warm for mid-October.
The Carolina low shifts northeastward out to sea Monday, and the Upper Midwest low heads northwestward into Canada, but the Atlantic high should remain largely in place, meaning continued dry conditions, and somewhat warmer as the Great Lakes low enhances the jet stream ridge overhead. Expect partly cloudy skies with highs in the upper 70s around Ithaca’s urban core, and mid 70s in the outlying towns. Monday night will be partly cloudy with lows in the upper 50s.
Heading into Tuesday, another upper-level low pressure system will pass to the west, this one slightly closer, northeastward over the Western Great Lakes instead of the Dakotas and Minnesota. This one could graze the Southern Tier just enough Tuesday night to trigger a few isolated showers, but it lacks moisture so no substantial rains are expected. Highs Tuesday will be in the upper 70s with partly cloudy skies, and overnight expect mostly cloudy skies with a few isolated light rain showers and lows around 60°F.
The high pressure rebuilds on Wednesday, and with the Great Lakes low riding over the top of the jet stream ridge and sliding into Eastern New England, the high will establish a new pressure center in a lobe over the Mid-Atlantic, re-stabilizing the local atmospheric column. Partly cloudy and dry conditions will resume with highs in the mid 70s. Wednesday night will see partly cloudy skies with lows in the upper 50s.
Another low pressure system passes over the Upper Midwest Thursday, riding along the edge of the jet stream ridge over us and reinforcing it with its warm front. This one seems likely to have more moisture available to it thanks to a more favorable connection to the Gulf of Mexico, and moisture ushered in from Mexico from what would be the remnants of what is now a developing tropical depression. The National Hurricane Season expects the storm to become a hurricane before making landfall (it would be called Hurricane Pamela, as the Eastern Pacific has its own lists of names) on Mexico’s Pacific coast as it moves northeastward.
As for the forecast itself, Thursday will be partly cloudy with highs in the mid 70s, and as the low gets closer Thursday night, expect cloudier skies with a few showers after midnight, and lows in the upper 50s.
Turning to Friday, it will be a mild day, though as the low heads into Canada, a plume of moisture will remain in the Mississippi River Valley and extend northeastward, allowing for less stable skies and some potential showers. Friday will be mostly cloudy with highs in the mid 70s, with a few scattered showers. Friday night will see somewhat more numerous scattered showers with partly cloudy skies and lows in the upper 50s.
For now, the weekend is looking unsettled and a little cooler as a low develops in the Mississippi River Valley and moves northeastward. With that moisture plume, it will be stronger. Keep an eye on this period, as it may the storm that ends up ushering in a colder weather pattern for the start of next week. For now, expect mostly cloudy skies Saturday with periods of rain and a high near 70°F. Saturday night will see showers and lows in the lower 50s, and Sunday will see colder air filter in, with highs in the low to mid 60s.
The cooler, more seasonable conditions likely to arrive for the start of next week appear to be relatively short-lived as the jet stream ridge rebuilds, though more to the west than previous. With warm, dry air brought poleward from Texas and Mexico, conditions are expected to be drier and warmer than normal as we head into the last weeks of the month. Upstream, a jet stream trough will result in cooler and wetter than normal conditions for the West Coast.