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UPDATE 5:15 PM: A frost advisory has been issued for Wednesday morning generally for the Roanoke Valley and regions south and east, those that were only brushed by freezing temperatures for a couple of hours back on Oct. 19. END UPDATE

Near-freezing temperatures are expected in the Roanoke Valley on Wednesday morning and sub-freezing temperatures are likely in many other parts of Southwest Virginia as a dry air mass and lengthening nights allow for rapid temperature dropping after sunset. Freeze and frost advisories have not been issued since cold mornings on Oct. 19 and 20 effectively ended the growing season in most areas. Still, if you have any plants you've put back outside in some of the sunny, warmer days, get them in tonight.

Well, this time last week I was suggesting that the week ahead would have pleasant temperatures and little or no rain. Instead, we had a couple of rounds of soaking rain. Let's try again this week: Once more it looks like a week of fairly normal temperatures (cool 30s and 40s in the morning, up in the 60s in the afternoon) with little or no rain, possibly through next weekend. There is more reason to be confident this week because there isn't a front hanging around along the coast and into the Gulf of Mexico that could serve as a focus for a low to develop, and high pressure looks to have firmer grasp on much of the nation. After last week's active weather week that included flooding rain, snow and severe weather across much of the country, this looks like a quiet week ... but we'll see if it changes.

If you haven't gotten in your Halloween activities yet, you're probably going to get soaked if it involves being outdoors the rest of this evening. A large area of rain moving out of West Virginia will soon overtake the area. While we saw some showers earlier, this will be a much more widespread and heavier rain ... though not a torrential one. Most places in our region are expected to get 1/2 to 1 inch. Once this rain pushes out, the week ahead looks like a treat, with dry weather, cool mornings and warm days. A prolonged period of mild to warm and dry weather may be in the offing the next 10 days or so ... but last week's projected dryness was spoiled by a storm that fired in the Gulf. We'll just have to see if there are any spoiler this week.

Winter is getting an early start in the Rockies and High Plains, where "the biggest snowmaker to hit Colorado's Front Range in October since 1997" is under way. Click here to read the Associated Press article. This same powerhouse low could become a severe weather producer the next couple of days  and also spread more heavy rain through the central U.S. It will pull a Pacific cool front through our region by the weekend, triggering a few showers around Halloween.

Kevin is driving through soggy Tennessee on his way back to Virginia today. He will be back Wednesday to talk about how this week's weather has defied expectations.

-- Erica Myatt

Getting past Saturday morning's showers, the advancing cool front is going to clear the way for a pretty classic late October week ... highs in the 60s, lows in the 40s, lots of sunshine and little rain. Sunday should be a good day for some leaf-peeping, as will much of the rest of the week, if you can make it out. There appear to be no hot, cold or wet extremes anywhere on the horizon.

A cold front pushing into our region and low pressure to our northwest is likely to trigger rainfall, especially tonight (sorry, high school football fans). This morning's rainfall projection map from the Hydrometeorological Prediction Center forecasts the potential for about an inch of rain in much Western Virginia through the next 48 hours. It might be just warm enough (in the 60s) that this front could even trigger a few thunderstorms with gusty winds. The first half of Saturday look soggy too, but rain should start to diminish into the afternoon. This front is more of a "cool" front than a cold one, as temperatures will cool down but not return to last week's frosty/mountain snow flurry levels, at least for the next few days.

Highs of 76 in Blacksburg and 78 in Roanoke today were well above the normal highs for this date of 63 and 67, respectively, but fell well short of the record highs of 81 for Blacksburg (1993) and 85 for Roanoke (1941). The morning started just a degree above freezing in Blacksburg at 33, 3 degrees below normal, and 42 at Roanoke, only a degree below normal.

We'll see a similar day on Thursday, though the cool start will be about 5 to 8 degrees warmer. 

Rain and cooler weather is still on the way over the weekend. A little further down the road, the 6-to-10 day and 8-to-14 day temperature maps from the Climate Prediction Center depict the progessive pattern well, as cooler than normal temperatures expand from the central U.S. early next week toward the east later in the week.

The timing isn't working out for anyone who wants a sunny Saturday. The sunny, warm days will be today and Thursday ... highs in the 70s, generally, after cool mornings in the 40s. Rain returns Friday with the next cold front -- Friday night football games look to be soggy right now -- lingering into Saturday.  Sunday, though, looks like it may be nice with sunshine, highs in the 60s, lows in the 40s, perhaps a good leaf-peeping day.

This is a result of the progressive jet stream pattern we are in, with fronts pushed across the nation about every 5 days, a few days warmup followed by a cooldown. For now, it appears most of the fronts are of Pacific origin, so no extreme chill-outs are likely. Very typical October weather.

Roanoke's official low fell to at least 32 briefly this morning, the first freezing temperature of the 2009-10 cool season. Blacksburg dropped to 28 and was below freezing for a few hours, indicating a growing season-ending freeze probably occurred in many areas away from the Roanoke metro area, especially north and west of Roanoke. While the first hard freeze of the year renders additional freeze warnings unnecessary, similar temperatures on Tuesday morning have led the National Weather Service in Blacksburg to issue a frost advisory for the second consecutive morning for locations from the Roanoke Valley south and east.