Tuesday greetings to one and all...
The forecast remains on-track today, as we'll be going through a couple dry days with warming afternoons. Here's the surface map for the day, courtesy of the HPC:
|HPC - Surface Map - Tuesday PM|
High pressure keeps the Gulf moisture locked away and separated from the north-riding jet stream. Dry weather influence extends all the way back to the Mississippi valley, but in these situations (especially in the summer) sometimes the mountains can allow for a little "dirtiness" in the broad area of high pressure. Call it cracks in the armor. Here's a case in point, from the NAM:
|NAM - Wednesday Midday - Clouds||NAM - Wednesday Midday - Precipitation|
Now, I wouldn't let this ruin (or change) your plans. Just know that if a few hours of the afternoon come with clouds, it's not a complete surprise. At this point, figure on more dry skies and sunshine over the next two days than not.
Now, we're still watching the end of the week with all it's unseasonable warmth and rainfall. Things are still looking the same there. The only important elements to watch for (in my opinion) are as follows: 1. The initial onset; 2. Any potential break in the action; 3. Total rainfall; 4. Potential for thunderstorms.
|NAM - Thursday PM||GFS - Thursday PM||Euro - Thursday AM|
The models are converging on a late Thursday arrival, but the image from the GFS is telling. It shows strong warm air advection out of the south-- breezy winds out ahead of the showers. This is notorious for preventing rainfall from reaching across the Big Sandy River and instead aligning it up through Kentucy and Ohio before becoming rather stubborn. This will need some monitoring, as folks in Charleston may end up drier for longer. The other thing to keep in mind with this first storm is that the bulk of the energy is passing us by to the west and north, so not a whole lot of total rainfall will be in the forecast.
2. Any break between storms?
|GFS - Friday PM||GFS - Saturday Afternoon|
The GFS is a good model on this one so far. After the first batch of weak-ish rain moves through Friday, about a 12-to-18 hour break comes in before the next stream of moisture stretches up the Appalachian trail. So far, that's looking to be the best time to sample the 60-degree air without dodging raindrops. Not much January in this forecast this week.
3. Total Rainfall (flood potential)
|HPC - Rainfall Forecast|
We're looking at much more rainfall west of the mountains (in Kentucky and Ohio). That stands to reason because of the drying effect southerly air has when rushing down the mountain slopes. Even still, 2" of rain stretched out across two storms and several days is not a lot of rainfall. On the above map, I would only be concerned about flooding possibilities in the southern Mississippi River Valley heading into the weekend.
4. Thunderstorm Potential - Let's not worry about this just yet. I have already penciled in some rumbles on the arrival of the second storm Saturday. This is a good bet just because of the final clash of air masses arriving then (anything that takes us from 20° above normal back down to reality comes with a little thunder. This is more the stuff of March, but hey, look at the maps... it looks a little like March, eh?
|Regional Radar/Satellite with Warnings Tracking||
From the Storm Prediction Center (below): Click For a Larger Image
|Activity Overview||Storm Outlook||Watches||Potential Watches||Storm Reports|
|Temperatures||HD Doppler Radar||Estimated Rainfall||Active Warnings|
|Click For Larger||Click For Interactive Radar||Click For Larger||Click For Larger|
Have a great day everyone!