Weather: Less rain and seasonal temperatures expected this week
ITHACA, NY – At the last check, just in the middle of the month, Ithaca-Tompkins Airport had recorded 5.73 ″ of rain so far in July. If no further rain were received for the remainder of the month, July 13 would be the wettest in 128 years of valid precipitation observations in Ithaca and surrounding areas. Yes, we are all tired of the rain.
This week will provide some sort of respite, but not completely. The risk of showers and thunderstorms will persist for much of the week, although the chances of heavy rains and flash floods are limited. Temperatures will be seasonal as we are trying to dry out a bit this week.
Light rains persist today, but here is a preliminary map of precipitation amounts for July 17, 2021. Here is the link to the reports: https://t.co/iQXlfkTk3p pic.twitter.com/KrRPNaHpDi
– NWS Binghamton (@NWSBinghamton) July 18, 2021
Your weekly weather forecast
The low pressure system responsible for yesterday’s frequent heavy rains is currently centered over upstate New York and Connecticut and moving slowly east, with some persistent light to moderate showers in the upstate , but nothing that has significant potential to cause flooding. With the heavy cloud cover of the storm system and the advection of cold air over the northwesterly winds, it’s a cool day for July, with high temperatures in the 60s above just over 70 ° F for most of Tompkins County.
With the slow movement of the thunderstorm system, the cloud cover will dissolve only slowly as we move towards Sunday evening and into the night, with a decreasing number of showers as the system continues to recede and our column. local atmosphere sets in. As cloud cover is generally expected to persist until Monday morning, and given the saturation of the soil (air humidification and slowing and limiting the air’s ability to cool), temperatures will not drop much this time. evening in the low 60s under those largely cloudy skies so dry, with fog likely in the valleys, so be careful if you are on the roads late tonight.
There will be constant clearing throughout the day on Monday, from mostly cloudy skies at sunrise, partly cloudy at noon, to a few persistent clouds at sunset. However, with saturated soil releasing moisture into the surface air, it will be quite heavy, and this surface moisture rising into the atmosphere with a weak short wave (instability pulse) passing aloft will destabilize atmosphere and allow a few scattered rain showers to occur. , as well as one or two isolated thunderstorms. Highs will be around 80 ° F. On Monday evening a few clouds pass and dry conditions, although wet again due to saturated soil slowly drying out in the air above. The lows will be in the lower 60s.
Tuesday will be warmer as the light northwesterly wind subsides and turns more westerly with a high pressure coming from the Midwest. Another weak shortwave bypassing the high will subside southward in upstate New York later Tuesday, again providing conditions for a few late showers and thunderstorms to set in as the highs reach the mid 80s along the lake and upper 80s elsewhere. The short wave will last through Tuesday night, allowing more showers and thunderstorms to develop with mostly cloudy skies. New precipitation will generally be less than a quarter of an inch through Wednesday morning. The troughs will be in the mid-1960s.
Wednesday will be unstable as the shortwave closes in a closed low (storm system) over southern New England as the high pressure slowly comes in from the west. Expect a mostly cloudy day early with a few scattered light showers, particularly east of Ithaca, becoming partly cloudy and drier as the day progresses. The peaks will be in the upper 70s. As the high pressure system continues to penetrate the Finger Lakes on Wednesday evening, the skies will continue to clear, with a few clouds passing overnight and lows in the upper 50s.
Thursday will be a largely dry day as high pressures persist for most of the day before a weak shortwave trough begins to plunge from the northwest towards the end of the day. Expect partly cloudy skies becoming mostly cloudy at sunset with a few isolated showers late in the day, with highs of around 80 ° F. Thursday night will be mostly cloudy with a few scattered showers, mostly after midnight, with minimums in the 1960s.
The weak trough will slowly move south on Friday, leaving the possibility of rain showers to persist for most of the day, but generally most areas will remain dry with partly cloudy skies, clearing up somewhat by sunset. Sun. Highs will be in the 80s. Friday night will be partly cloudy and dry, with lows in the 60s.
Conditions will remain volatile until the weekend, although no significant rain is expected. Saturday will be mostly sunny with highs in the 80s, and a weak short wave moving from Saturday evening to Sunday will usher in some showers and mostly cloudy skies overnight with lows in the 60s, but in general it will remain dry with partly mostly cloudy skies and highs again in the low 80s on Sunday.
The large-scale weather model identified in most medium-range forecasting models identified a pronounced ridge in the jet stream over the high plains, with unusually warm conditions expected over Minnesota and the Dakotas. This fairly wide ridge is less pronounced over the Pacific Northwest and will allow the Pacific flow to bring cooler-than-usual air and potentially much needed precipitation into the southwestern desert and parts of it. California.
However, for us in the northeast, downstream of the ridge, we will get the trough part of the jet stream – think of the mid-latitude jet stream as a rope going up and down, where there is a wave towards the top, there is always a corresponding wave in the rope towards the bottom. As a result, cooler than usual conditions are expected to end in July. Incoming continental air will also be on the dry side even as storm systems slide along the jet, so these weather circumstances largely cancel out. Overall, expect normal to slightly drier than normal conditions which, like our friends across the country, will be a welcome respite.