Kevin Myatt is The Roanoke Times' weather columnist.

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Current Forecast Track of Tropical Storm Bonnie: www.tpc.ncep.noaa.gov/ftp/graphics/AT02/refresh/AL0204W+GIF/120903W.gif

Current Forecast Track of Hurricane Charley: www.tpc.ncep.noaa.gov/ftp/graphics/AT03/refresh/AL0304W+GIF/120913W.gif

National Weather Service, Blacksburg: www.erh.noaa.gov/rnk/

4:45 p.m.

The bulk of Bonnie’s action appears to be hitting areas from Roanoke east. Tornado and flood watches remain in effect roughly from I-81 eastward, and at least one tornado warning has been in effect in the Danville area. The spin produced by a landfallen tropical system often produces enough atmospheric shear to spin off a few twisters.

In Roanoke, we will probably see some showery weather and maybe even a few thunderstorms tonight, but it looks like the heaviest rain will be to the east. This may be the pattern that is renewed with Charley’s passage into our our area on Saturday. Charley’s biggest threat is to Florida, where thousands are being ordered to evacuate in advance of what is expected to become a strong hurricane strike in a western Florida region that rarely experiences strong landfalling hurricanes (eastern Florida and the Panhandle usually get more of the action.)

With tropical moisture and a stalled cold front, it looks like we’re almost certain to have more wet weather over the next 48 hours, though hopefully not the kind of flooding that we had feared.

10:30 a.m.

Tropical Storm Bonnie is nearing the Florida Panhandle with 55 mph winds. It appears unlikely that Bonnie will be a hurricane at landfall. She very quickly becomes a concern of ours as her plume of tropical moisture could bring flooding rains to some parts of our region tonight.

A stalled cold front just west of us -- roughly along the Virginia-West Virginia line -- will act as a guidewire for Bonnie, which will slide up just in front of the front. This has been a common setup for some big rains in our history, including the infamous Hurricane Juan in November 1985. However, Bonnie will be moving much faster than Juan was, pushed along by a vigorous autumn-like jet stream dipping down from Canada. It's a role reversal from what is usual: the August tropical storm speeds along, while the November hurricane dawdled in 1985.

The front, however, will act as a focusing mechanism for rain, as tropical moisture is slung behind whatever's left of Bonnie's circulation into the leading edge of a mound of cool air. It's that classic tropics-tundra collision I keep harping about, and it could result in some big rains. The National Weather Service in Blacksburg has posted a flood watch through noon Friday for the possibility of 2 to 4 inches of rain, particularly along and just east of the Blue Ridge. Looking at this morning's radar (http://www.erh.noaa.gov/radar/latest/DS.p19r0/si.kfcx.shtml we may get a ton of rain today just from the front before Bonnie even arrives.

Here is the Hydrometeorological Prediction Center's expectation on rain from 7 a.m. today to 7 a.m. Friday: www.hpc.ncep.noaa.gov/qpf/fill_94qwbg.gif.

Then, we have watch Charley's track out of the Caribbean. Charley promises to be a bigger deal for whatever section of coast it hits than Bonnie will be. Charley already has 85 mph winds with the threat of more strengthening.

Forecasts continue to bring Charley on a similar but slightly more eastward path than Bonnie. As of this morning, the National Hurricane Center's forecast takes it right into Tampa Bay on Friday, which would be an emergency manager's nightmare for many reason -- dense population, storm surge entering a tight bay, and people who haven't experienced a direct hurricane strike in decades.

But there are still some questions about Charley's path. The concerns center on exactly when the low pressure trough over the eastern U.S. will catch Charley and turn him northward. A slightly more westward path could create an especially severe flood threat for our area, especially if Bonnie does what she's expected to with rain tonight. Having the remnants of two tropical systems moving across us within 36 hours would possibly be unprecedented.

For a while Thursday evening, there was speculation that Charley could be left behind by the eastern U.S. trough that will eventually bring us another shot of October-like weather, and that he could spin westward toward Texas. That appears much less likely today. Charley looks like a Florida strike with a path across the East Coast states similar to Bonnie's but maybe a bit farther east. It's close enough that the first half of what was supposed to be a spectacularly beautiful weekend will probably be soaked.

We should know more about Charley by this time tomorrow.