The rest of today will be quite warm and muggy… we’ll be monitoring the potential for some isolated thunderstorms to develop during the course of the afternoon – those that do could produce heavy rain, frequent lightning… perhaps some hail and damaging wind. The greatest threat for widespread storms comes late evening and overnight as a cold front moves into the region.
As the cold front basically stalls across Southern New England, we’ll continue with unsettled/wet weather tomorrow and perhaps into early Thursday. Due to this, the threat will increase for poor drainage flooding where the axis of heaviest rain sets up. Some towns may receive 1 to 2 inches of rain, with locally higher amounts.
With regard to Irma, the now Category 5 storm has 180 mph sustained wind (as of 11a Eastern) and is heading toward the northern Leeward Islands. This is the strongest hurricane, outside of the Caribbean and Gulf of Mexico, in National Hurricane Center records. The last time a hurricane had wind stronger than Irma's (to date) was with Wilma, in October of 2005 when the highest sustained wind was 185 mph. Irma also ties the wind speed of both Rita and Mitch.
In addition to Irma and its heels, as of 11a Eastern, there now also Tropical Storm Jose. It is forecast to become a hurricane but is no immediate threat to land.
Meteorologist Mark Dixon
MILD & MUGGY START
This morning we're caught between high pressure over the western Atlantic Ocean and a strong cold front over the Great Lakes. That means continued southwesterly winds, which are pumping more warm and humid air into Connecticut. That held our low temperatures this morning in the 60s, which is quite the change from what we saw over the weekend when we saw a record low of 41 degrees at Bradley Airport Saturday morning!
WARM & HUMID WITH PM T’STORMS TOMORROW
Although yesterday marked the unofficial end of summer, as just about everyone will be back to work and/or school, today will feel very much like a summer day! We're starting the day off with partly sunny skies, and expecting partly sunny skies through the day today. That will allow temperatures to climb well into the 80s inland while dew point temperatures stay in the 60s. The good news is that there will be a gusty southwesterly breeze, so it won’t feel oppressive outside. That breeze will also keep shoreline towns in the upper 70s and lower 80s today.
But by late this afternoon and this evening, the cold front will be close enough to trigger numerous showers and thunderstorms. The front will be quite strong, so some thunderstorms that do develop could become severe! Western Connecticut will be at the greatest risk for storms late this afternoon, as that area will be closer to the cold front. For that reason, the Storm Prediction Center has put that area in the “Slight Risk” category for severe weather and the rest of the state in the “Marginal Risk” category.
The main threat from these storms will be strong winds, but we may see some hail and heavy rain with a few of the storms. We will certainly keep you updated as the thunderstorm development picture becomes clearer today!
While the front will pass east of us tonight, it will stall nearby, so shower and thunderstorm chances will continue. Low temperatures will still be fairly mild, with lower 60s expected.
RAINY & COOLER WEDNESDAY
The frontal boundary will become parallel to the upper-level steering flow Wednesday, which will prevent it from making much eastward progress. At the same time, a wave of low pressure will develop along the front and move northward. That means clouds and periods of rain for us tomorrow, some of which could be heavy at times. Since we will be on the cool side of the front, our high temperatures will struggle to reach 70 degrees, solidly below the average high of 78 degrees for September 6th! Rain chances will continue into tomorrow night as temperatures drop into the upper 50s and lower 60s.
IMPROVING WEATHER THURSDAY
By Thursday, the cold front will finally progress far enough eastward to allow our weather to improve. While there will still be some leftover rain in the morning, it will move out by afternoon and skies will begin to clear out. The clearing will allow our temperatures to rebound into the middle 70s. Plus, the humidity will be low, so it will feel quite nice outside! It will also set us up for a cooler night Thursday night, with low temperatures in the lower 50s, with some upper 40s in the normally cooler spots.
SHOWERS POSSIBLE FRIDAY AFTERNOON
Friday will feature some instability in the atmosphere thanks to an upper-level low pressure system over southern Canada. That will bring the chance for some afternoon showers with the heating of the day, though we think most of the activity will remain to our north. Temperatures will be on the cool side Friday afternoon, as the Connecticut River Valley and the shoreline will only hit the lower 70s while the higher elevations will fail to get out of the 60s.
Any showers will clear out Friday evening once the sun goes down. As the skies begin to clear, temperatures will drop into the 40s in most of the state – lower 50s along the shoreline – so it will feel very much like fall!
DRY & COOL SATURDAY & SUNDAY
A large area of Canadian high pressure will be in control of our weather this weekend. That means mostly sunny skies and very low humidity – dew points in the 30s and 40s. However, the air mass over Connecticut will be quite chilly, so high temperatures will only reach the upper 60s to near 70 degrees over inland Connecticut both Saturday and Sunday despite the sunshine! The Interstate 95 corridor might be slightly warmer, but still cool for early September as highs will reach the lower 70s both days.
Saturday night will be clear and quite chilly as temperatures drop into the 40s in most places. A few upper 30s will even be possible in the typically colder spots. The high pressure system will be nearly overhead, setting us up for an even colder night on Sunday. Many towns will likely see temperatures dipping into the 30s, while even the normally warmer spots will fall into the 40s! If you are planning on going to the fairs in Bethlehem, Hebron, or North Haven either night, you will want to bring extra layers of clothing.
GORGEOUS DAY MONDAY
After a chilly start Monday morning, sunny skies will allow our temperatures to rebound quite nicely! High temperatures will reach the lower and middle 70s and the humidity levels will still be very low, so it will feel great outside!
We are keeping very close tabs on Hurricane Irma. The storm is moving westward across the Central Atlantic and is currently about 320 miles east of the Leeward Islands. Irma is a Category 4 hurricane with winds of 145 miles per hour. Irma may continue to strengthen over the next few days and it will be a threat to the Leeward Islands by the middle or end of this week. Eventually, the storm may be a threat to the east coast of United States, but the uncertainty regarding this issue cannot be understated. If it impacts the eastern U.S., the timing would possibly be Monday or Tuesday of next week – six or more days from now. Since impacts from the storm are possible here in New England, we will certainly monitor this storm closely!
Chief Meteorologist Bruce DePrest with Scot Haney
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