ITHACA, N.Y. — It’s the front that overstays its welcome. A neatly stationary frontal boundary portends a wet and potentially stormy pattern for much of the work week, before finally clearing out in time for the weekend.

Precipitation, mean sea level pressure and 1000-500 mb thickness (temperature proxy) for 8 PM Thursday evening. A large wave of low pressure will result in hours of moderate to heavy rain across the region. GFS Model output courtesy tropicaltidbits.com

Your Weekly Weather

It’s been raining practically incessantly through the day this Sunday, and you can thank (or curse, your choice) a cold front that pushed southward through the region before stalling out over the Twin Tiers. The front is one issue, but it also works as a channel of instability, allowing storms to ride along it and create multiple waves of rain and thunderstorms over the next few days.

Sunday night will allow for at least some clearing out, as the latest wave of moisture moves eastward and the front sags into Pennsylvania, giving another geographic distance between us and it to allow for some clearing tonight and into Monday. The showers should taper off, but skies will remain mostly cloudy this evening, with lows in the lower 50s. Thanks to the clouds overhead and all the moisture keeping the surface layer of air humid, holding back its ability to cool off with the loss of daytime heating, there’s a fairly good chance for some fog tonight, especially in the usual valley areas. Use caution when traveling this evening, especially between midnight and daybreak.

Monday should remain dry and mostly cloudy for most of the day, though some early afternoon breaks of sun will be more likely as the sun manages to burn away some of the low-lying clouds along with any fog present. Temperatures should make it into the upper 70s by mid afternoon before the cloud cover begins building back in again as the front starts inching its way back northward. Yes, it’s like the guest that has overstayed its welcome, but the weather doesn’t worry about social cues. Monday night will be mostly cloudy, with rain showers building into the Southern Tier by morning. Lows will be around 60 °F.

Tuesday will be an unsettled day as the front approaches again, and with it some showers and thunderstorms as weak disturbances travel along the trough. The best chance for rain will be in the late morning to mid afternoon, but since these trigger disturbances will be quick moving and weak, don’t expect a washout, and the thunderstorms shouldn’t be severe, just your typical rumbles of thunder and associated downpours. Highs will be in the upper 70s, with some clearing late. Tuesday night will be partly cloudy, a break between disturbances as the front lingers, with a low in the upper 50s.

The west-east flow of moist, unstable air continues into Wednesday as another disturbance moves in during the afternoon hours. Expect mostly cloudy skies with scattered showers and thunderstorms, especially from the 1-7 PM timeframe. A few of these may be strong or well organized, so keep an eye out for a severe thunderstorm watch or if need be, severe thunderstorms warnings. Highs will top out in the upper 70s with mostly cloudy skies between storms, and it will be a touch on the muggy side. Wednesday night will be mostyl cloudy as we’re once again between disturbances, so expect dry conditions and lows in the low 60s.

Thursday is the one day that truly looks like a washout, as a broad and powerful storm system moves in from the southwest and sweeps across the Northeast and Mid-Atlantic. This broad system will channel very moist air into the region, and with the unstable atmosphere, there will be potential for multiple heavy downpours. Weather service offices will be monitoring this event closely for the potential for flash flooding in multiple locations across the Southern Tier. The rain should arrive in bulk by late morning, and continue through ther afternoon and into the night before clearing out after midnight as the low continues its trek eastward. Expect periods of rain, overcast skies otherwise, and highs in the mid 70s. Thursday night will be rainy early, with cloudy skies starting to break up late, and lows in the upper 50s.

Friday, the first day of astronomical summer (summer solstice, when the sun is directly over the Tropic of Cancer at 11:54 AM), will allow for some drying out now that the stationary front and the large moist storm system have been shoved out to the Atlantic. Expect mostly cloudy skies to give way to partly cloudy skies by afternoon, with a low in the mid 70s thanks to the northwest breeze. Friday night will be dry, partly cloudy with lows in the mid 50s.

This far out, the weekend is looking dry and pleasant as high pressure takes grip of our region. Expect ample sun with just a few passing clouds Saturday and Sunday, with temperatures in the upper 70s Saturday and low 80s Sunday. Night time lows will be in the upper 50s.

Graphic courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking into the start of summer, a trough of cooler air will prevail over the western United States, and a dome of hotter air centered over the Southeast (which will go just great with their summer humidity). But here, where the ridge will be our footstep, temperatures should stay fairly close to normal. Precipitation will be near to a notch above normal for the period as the prevailing storm tracks will be over the inner Mountain West and Midwest, and will generally dispactch storm systems out eastward to our south over the mid-Atlantic states.

Brian Crandall

Brian Crandall reports on housing and development for the Ithaca Voice. He can be reached at bcrandall@ithacavoice.com.