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On the excitement scale, the weather this week rates very low. Maybe, just maybe, there will be a scattered shower or storm a day or two later this week, with Sunday showing the best chance right now. But on the enjoyment scale leading into the Fourth of July weekend, this week should rate very high for almost anyone. Days will see highs in the upper 70s to mid 80s, very slowly warming through the week, with relatively low humidity. Nights will be cool with lows in the mid 50s to low 60s most nights in most places. The days will be warm enough for kids to hit the swimming pool but not unberably hot for those doing outside work. Our air flow is generally from the northwest, which is the cool, dry direction, with little input of hotter, more moist air from the Gulf of Mexico or Atlantic.

Enjoy this now. Summer is young, so a run of humid, stormy weather or sizzling hot weather still has plently of time to develop.

The weather pattern has been pretty stagnant this week, with hot high pressure in the south-central U.S. deflecting any fronts and significant storm systems up and over it. Here in Southwest Virginia, we've been on the eastern edge of the high, so we've not really got into the really hot stuff but have been a little above normal with very little rain, the most occurring today with a few scattered thunderstorms aided by a passing weak front. There are signs of a pattern shift later this week, with the high pressure in the central U.S. shifting westward. This would allow its clockwise circulation to pull down some cooler air from Canada toward our region by mid to late next week. The 6-to-10-day temperature forecast map from the Climate Prediction Center reflects this expectation, with its blue colors over most of the nation east of the Mississippi River (except Florida and parts of nearby states). As for rain expectations around the Independence Day Weekend: we're on the borderline between normal and above-normal.

But there is something lurking that could play with this forecast. The National Hurricane Center is watching a system in the northwest Caribbean that has at least some chance of developing into a tropical storm as it enters the Gulf of Mexico. Something to watch, but nothing to lay a heavy bet on, yet. The storm's name would be Ana if it becomes a tropical storm.

With moisture increasing on southwesterly winds, there might be a few afternoon thunderstorms on Thursday, and likely even more on Friday as a cold front moves in. While a few spots may get soaked under the heavier thunderstorms (and some gusty winds and hail are possible, too), it does not look like there will be any widespread soaking rainfall. Beyond that ... still looks mostly dry into early next week, and pretty hot with highs hovering around 90.

Our 5-day outlook for rain potential from the Hydrometeorological Prediction Center shows only light rainfall amounts in Southwest Virginia through the weekend, and even that is probably related only to some scattered showers and thunderstorms that may develop late in the week over the mountains as some moisture returns. There are no copious supplies of Gulf moisture in sight as dry, northerly air flow only slowly gives way to west/southwest winds that will be coming from under dry high pressure to the west, so humidity values will only gradually increase as a Gulf moisture only trickles in.

Four of the Virginia Tech storm chasers ... instructor Dave Carroll and students Andrew Smith, Samantha Huddleston and Nathan Horne ... plus Maria Floyd, a South Carolina resident who helped lead the trip back in 2004 and 2005, made a sequel storm chase trip last week to capture a few days of a favorable severe weather pattern from the Northern Plains and Upper Midwest into the Ohio Valley. Some of what they found can be found by linking here to the Hokie Storm Chasers page. The original trip back in May -- that included 12 to 16 chasers at different times -- caught a lull pattern for severe weather, with only 3 storm days and really only one definitive supercell.

I didn't make this trip ... I was out of state a few days, but I was visiting family in Arkansas this time around.

We wouldn't have said this last year during the drought, but we could use a few days of dry weather. And that's what we're going to get this week as a strong low to the east circulates dry north winds into the region for the next few days. That will slowly give way to a hot, dry southwest flow which will only slowly rebuild moisture levels by mid to late week. So those of you who have been wanting dry weather after so many periods of rain ... you're very likely to get your wish.

So far, Southwest Virginia has mostly dodged the potential for powerful thunderstorm clusters to move into the area from the northwest. But the region is under a slight risk of severe weather once again today, for the possibility that new storms could fire in the unstable air mass as disturbances move through and a cold front approaches, with strong winds as the primary threat.

Southwest Virginia is in a slight risk zone for severe weather both today and Saturday. It's a matter of watching each sucessive thunderstorm cluster moving southeastward out of the Upper Midwest and Ohio Valley. The next one to watch is diving through West Virginia now, and might come into all or part of Southwest Virginia by early afternoon.  Gusty winds will be the main severe weather threat ... and there will be the ever-present threat of unwanted locally heavy rainfall. With temperatures possibly challenging 90 and dew points in the 60s to near 70, there is plenty of instability and moisture available to charge storms today.

National Weather Service-Blacksburg radar

Regional and national radar

Although there is a slight risk of severe weather today, it may in fact be a drier day overall today with the bulk of rain and storms both east and west of Southwest Virginia. Friday, during the day, also looks fairly dry for now, with only scattered showers and thunderstorms. But there is growing concern that severe weather organizing in the Ohio Valley on Friday will affect the region Friday night and Saturday, which could mean another shot of widespread heavy rain, too, before cooler and drier air settles in for early next week.

Here's a link to a story in today's Roanoke Times about rising rivers in the area

A flash flood watch is in effect until 6 p.m. today as a warm front working slowly northward is the focus for yet more rain and thunderstorms. It used to seem like I was writing "drought" in every column and blog entry ... how much that has changed. That warm front will introduce a summery amospheric regime that could push us well into the 90s by Friday and Saturday under dry sunshine. Somehow I don't think many folks will complain about that.

A cold front pushing in late Saturday or early Sunday will end that spell, though, and could take us back into a pattern of frequent thunderstorms next week.