Upper Ridge Settles In

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The weak upper low that you see spinning over East Tennessee and extreme western North Carolina kept the weather somewhat unsettled along the coast of the Southeast US yesterday, with the upper ridging and lack of sufficient moisture helped to keep showers in check for North and Central Alabama. That weak upper low is expected to move northeastward today, and as the surface high shifts slightly eastward, moisture should increase a bit. While this is a subtle change, it should be enough for us to see ann isolated shower or two in Central Alabama today. Moisture remains deeper southeast of us, so the greatest potential for showers should still be over southern Alabama. These showers will be driven by the heat of the day, so expect them to diminish as the sun begins to set.

The upper ridge is going to be the main feature in our weather pattern for the first few days of the upcoming week. But by Wednesday and into Thursday, the ridge begins to migrate westward as a strong short wave comes out of South Central Canada and digs into the eastern half of the country. The trough will be slow to dig into the eastern half of the country with a substantial trough becoming established by next Sunday. Model consistency within the GFS continues to be good as is the consistency on this feature between the GFS and the European model. Because of the consistency in this solution, forecast confidence is high.

As the trough sharpens up next Sunday, we should see a cold front coming into the region. There is still some uncertainty as to exactly how far south the front will come, and at this time, I do not expect to see it push all the way through Central Alabama. What the trough will do is to drop thicknesses a good 60 meters or so which will put highs once again back into the middle and upper 80s. We should also see better chances for showers with showers becoming more widespread. It is interesting to note that the GFS Model Output Statistics, or MOS, does not really show what I would consider to be a significant change in temperatures or precipitation probability. The drop in thickness along with what should be increased cloud cover seems likely to put highs at least back into the upper 80s, a nice thing to see in late June.

Because the westerlies remain well north of us, traveling weather systems will keep the most active weather in the North Central US to New England for the next three days as outlined by the SPC slight risk area. Further south, the tropics remain quiet for now.

Looking into week two, the trough developing by next weekend is forecast by the GFS to close off over the eastern Great Lakes by July 3rd, and eventually weaken as it is replaced with an upper ridge. This would return us to a weather pattern much more typical for summer.

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Thanks for tuning into the Weather Xtreme Video. Be sure to catch my forecast this evening on ABC 3340 at 5 and 10 pm. James Spann will be back from vacation on Monday with the next edition of the Weather Xtreme Video. Godspeed.

-Brian-

PS This coming week is Lightning Awareness Week in the US.

Category: Alabama's Weather