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It appears that the airport at Hot Springs ... actually located on top of the mountain above the town and The Homestead ... experienced some snow overnight and this morning as temperatures dipped to just above freezing.

And it appears almost certain that Roanoke will set an Oct. 15 record for coldest high temperature today ... and it likely won't even be close. We're sitting at 44 this morning, the record is 53 set in 1978 and 2002, and rain is moving in as cold air damming maintains its hold on our region.

A cold front and some more snowflakes, especially in the higher elevations, are still on the way for Friday and Saturday. If a flake or two blows into the Roanoke Valley, Saturday morning would be the best bet.

Chilly, rainy weather is on tap through the weekend with some cold-air damming from the northeast and an active jet stream bringing a series of storms across the country that will sling Gulf of Mexico moisture over that cooler air. The rain is on the Roanoke Valley's doorstep right now (click here for local National Weather Service radar).

And by the weekend, higher elevations in our area may see the first snowflakes of the season behind a cold front.

It will take me a few days to get back in the weather groove. I've barely paid attention during the past week after being in Arkansas for my dad's funeral.

I do know that, suddenly, the weather pattern looks a lot like winter.

Blacksburg's morning low reached at least 37, and Roanoke's dipped to at least 43. I say "at least" becasue sometimes a later analysis reveals a lower dip. As they are, these mark the lowest temperatures at those sites since May 20, when Blacksburg was 36 and Roanoke was 42 (after being 33 and 37, respectively, the previous day). You can click here for various other weather observation sites in the area, at least one of which dipped as low as 30. (I'll let you find it.)

While most mornings the next week are expected to be seasonably cool in the 40s and low 50s, daytime highs will creep back into the 70s. So this taste of frosty chill is, for now, a brief one.

A thin line of showers marks the arrival of the next cold front that will breezy conditions by afternoon and even cooler weather by tonight. Don't be surprised to see a brief shot of rain during the day, but most of it probalby won't make it over the mountains because of the downsloping nature of the westerly winds.  Behind the front, we will have two or three days of highs in the 60s and lows in the 40s, perhaps even a few readings in the 30s in some elevated valleys and very high elevations. It could indeed be sweater weather the next few mornings.

The last two weeks of humid dreariness is colliding with an advance of cool, autumnlike air from Canada, and the result will be some pretty robust rains over the next 36 hours or so. So far today we've mostly seen light rain and drizzle in Southwest Virginia, and that is likely to continue off and on overnight and into Saturday. By later Saturday and into Saturday night, the cold front may be able to force the moisture upward into some more vigorous showers and thunderstorms, which could have heavy rain. The 2-day rainfall map from the Hydrometeorological Prediction Center is projecting widespread 1.5 to 2-inch rain fall amounts across most of Western Virginia through Sunday, with even heavier amounts just to the west in eastern Kentucky and West Virginia. Giles and Bland County, plus most counties west into the coalfields of far Southwest Virginia and southern West Virginia, are under a flash flood watch for this threat of heavy rain.

The path to some cool, clear, dry, autumnlike days next week leads right through this soggy mess. Be sure and take the rain gear and something a little warm if you're going to the Virginia Tech-Miami game on Saturday, as temperatures may hang in the 50s in Blacksburg during what could at times be a downpour.

I'm not about to say today will be the last 80-plus day of 2009 ... we're usually good for a few of those in October or even into November. But it may be the last sultry summerlike day for quite a while, with highs in the 80s and enough humidity for showers and storms to be a threat in the afternoon. A backdoor cold front from the north will cool things down considerably for Friday, then rain will do the same for Saturday before a stronger cold front from the northwest arrives to introduce a much cooler, drier air mass. So, yes, a taste of summer today will be giving way to more fall-like weather by next week.

Well, I see didn't miss much being out for four days. I actually got in the middle of the most intense thunderstorms I've seen all year waiting for my mother to finish shopping at Wal-Mart in Jonesboro, Arkansas, on Monday. There was gusty winds, extremely heavy downpours, hail and lots of close cloud-to-ground lightning. My drive back was almost totally dry except for the last 30 miles, where I started hitting the drippy, drizzly stuff at Christiansburg, this dreary upslope stuff that's going to be hard to shake the next couple of days.

I didn't miss much locally, that is. Georgia got caught in some incredible training downpours that caused deadly flooding and the Colorado mountains got their first substantial snow of the season, a kind of kickoff for autumn in the U.S.

The most important large-scale development is that we're finally going to see substantial jet stream dynamics moving over our region by the weekend, breaking us out of this stagnant soupy pattern into something a little more fall-like. A major frosty leaf-changing cold snap, it is not likely to be, but next week looks to at least start drier and cooler than this.

Thanks for the foliage discussion while I was away. I'll get back on that subject soon.

Largely because of weak upper-level steering winds, the slow-moving low in the south-central U.S. simply hasn't delivered on its rain potential for our region the last two days. Some sunshine is likely on what will likely be a very nice Saturday for outdoor activities. But by Sunday, the meandering low will finally be kicked out by another low digging in from the north. This will restore the southeast winds, the low clouds, and an increasing chance of showers. Next week could follow a very similar pattern as this week, with the new low likely to also stall and meander in the south-central U.S. before finally being kicked out late in the week. 

More days than not over the next 7-10 or so will be dreary, so enjoy Saturday's sunshine.

An upper-level low slipping southeast from the Ohio Valley will likely trigger widespread showers and thunderstorms today, especially from the Roanoke Valley westward. The atmosphere is pretty thick with moisture, so locally heavy rain will be possible, as will gusty winds and some hail in the stronger storms, especially with a pool of cold air aloft that these storms may be able to bubble up into.  The best chance of hail or high winds is over far Southwest Virginia no farther east than Wytheville, and not enough to rate a slight risk of severe weather (only a "See Text") by the Storm Prediction Center. 

The coastal low is still there, though more offshore and weaker. Nonetheless, it is likely to affect our weather Thursday and Friday, as it meanders a bit back to the west, by pulling cooler air from the northeast into our area. Though the forecast for Thursday now is for highs in the 70s, it might not get out of the 60s if a thick bank of moisture, fog and clouds develops.

Speaking of the coastal low, David Sobotta, who goes back and forth between homes on a mountain overlooking the Roanoke Valley and the Crystal Coast of North Carolina (he has a local blog, View from the Mountain), measured 8.3 inches of rain on Labor Day from the coastal low. Here is a blog post he made about that.

The good news is that the National Hurricane Center no longer considers this low even a slight tropical development risk ... and distant Hurricane Fred is not going to get close to any significant land mass before sputtering out in the high-shear upper winds that are killing Atlantic tropical systems left and right this season.

Though the Atlantic tropical season has been underwhelming so far, there is a low-pressure system off the coast of the Carolinas that is being watched by the National Hurricane Center. However, it is given a low chance of development into a tropical system because upper-level winds remain too strong. So this probably won't become a tropical storm or hurricane. We'll be between this system and an upper-level low to the west, and thus there could be showers and some thunderstorms each day this week.  National Weather Service radar has shown much of the rain overnight and this morning over West Virginia and the coalfields area of far Southwest Virginia.

A system in the eastern Atlantic just off the African coast is given a high chance of development by the hurricane center. It will likely become Tropical Storm Fred (and probably in time, Hurricane Fred -- unless the East Coast system somehow beats it to tropical development, which would push us down the list to Grace). It will be many days from any possible effects on the coast of the United States or any other North American or Caribbean nations.