Heat And Storms: Must Be July In Vermont, Also, Will This Be First Rain Free Weekend Since Last Year

A small sea of day lilies in St. Albans, Vermont this
morning gear up for a hot, humid Sunday. 

 It seemed strange Saturday morning waking up to cool temperatures in the 50s and finding parts of Vermont were under a heat advisory. 

But that heat advisory is indeed in effect for this afternoon in the Champlain and lower Connecticut River valleys and some low elevations in southwestern Vermont today as we get ready for a brief but pretty strong squirt of hot weather.

The surging heat struggling to make it toward Vermont Saturday as a weak warm front lingered to our north in Quebec. 

That sent some clouds down our way in the afternoon, tempering readings that had been expected to reach the mid-80s. Instead, at least in northern Vermont in was in the 70s to near 80.  

A few of those northern Vermont clouds yielded sprinkles. A few rain drops fell late Saturday afternoon here in St. Albans. So in a sense, that ruined the chances of having our first precipitation-free weekend since mid-December. 

But not officially. Not so much as a single raindrop fell at the National Weather Service office in South Burlington, which is where this rainy weekend streak is being measured. So the 28 consecutive weekends with precipitation will end today unless at rains at the NWS office.

TODAY 

It could actually rain in Burlington today, which is a change from previous forecasts, though odds are still somewhat tilted against showers or storms there today.  

This morning, many of us woke up to a fairly comfortable dawn. Temperatures bottomed out near 60 in most places in Vermont away from the Champlain Valley. . Lows this morning in the Champlain Valley were in the armer low 70s. 

Temperature and humidity will rapidly increase through this morning as the hot blast of air flows in. In areas where the heat advisory is in effect, actual temperatures should hit the low 90s with a heat index in the upper 90s. 

Elsewhere in Vermont it will be uncomfortably hot, too.  It won't be as bad as that extreme, record breaking hot spell on June 23-24, but you will still want to take it easy.

The change in the forecast is the risk of a few thunderstorms this afternoon, especially over the northern half of the state. Previous forecast had indicated too much sinking air and dry conditions high overhead for any storms or showers to form.  

Now, we're not so sure. Some computer models have scattered storms developing while others have practically nothing this afternoon. It's a waiting game to see which ones are correct.  Already, an odd little downpour formed seemingly out of nowhere around  St. Albans shortly after  9 a.m. this morning. 

Almost anytime you have heat and humidity, there's always a chance a storm could fire up. If you have outdoor plans today, go ahead and enjoy, but just be ready to seek shelter inside a building, away from potential lightning, just in case.

MONDAY

There's a much better chance of showers and storms Monday as a weak cold front slowly sinks southward and approaches us from Quebec.

It'll still be very warm and quite humid, with temperatures in the 80s, with low 90s south. With the cold front pushing into that, we could get some decent storms. 

There's a fairly low but still real chance a couple storms could be severe, and an equally low but real chance we could have a few local flash flood issues. 

The biggest threat would be a microburst here or there. A microburst works as follows: 

Strong updrafts feed thunderstorms. Those updrafts also suspend lots of rain drops and hail stones up in the storm. Some storms will reach a point at which the updraft collapses, and all that rain comes down in a  great, high speed gush of downward moving air and water.

That gush hits the ground and causes an small swath of damaging winds and torrential rains. The damage area from these things are usually at most a mile or two wide and a few miles long. But they mean business!

Individual storms Monday should have a fast enough forward motion to prevent flash floods. The problem is the cold front itself will just be crawling southward at a snails pace.

Which means you could get one thunderstorm after another traveling west to east over the same path just south of the cold front. If that happens, a particular spot could get a few thunderstorms, and enough downpours to cause some local flash floods. At this point, it looks unlikely for Monday, but still definitely possible. 

The best chances of storms are in the northern half of Vermont, which will be closer to the front. 

BEYOND MONDAY

The cold front, such as it is, will still be struggling through southern Vermont Tuesday, so the best chances of more storms are down that way.  One slight wild card is soon to be former Tropical Storm Chantal.

It came ashore in South Carolina early today with top winds of 50 mph. Not a huge storm. Chantal's remnants are forecast move northeastward along the coast into or near southern New England midweek. 

Former Chantal's path could possibly slow the cold front down even more. We'll see.

In any event, this isn't exactly a powerhouse cold front. Temperatures for the rest of the week will remain near or a little warmer than normal for the rest of the week. We might get a bit of a break from the humidity Wednesday, but it will be brief.

It looks like humid, unsettled weather will probably return by Thursday.