6/17 – Britt’s “Oppressive” Friday Afternoon Forecast

Bottom line up front…it`s going to be hot. Heat Advisory will be repeated for today. We`ll be going day to day on the actual product issuances, but a Heat Advisory or Excessive Heat Warning will necessary Saturday. Our Excessive Heat Warning Criteria is 113F Heat Index or higher. If a backdoor cold front fails to move into the area Saturday night and Sunday, we can`t rule out the necessity on Sunday, either.

Upper troughing over the Great Lakes will cause the upper ridge to reorient more north-south over the Mississippi River Valley and Great Plains over the next 48 hours or so. As the trough digs along the Atlantic Coast, it will push a backdoor cold front toward the area on Saturday. Cold front won`t exactly be an accurate description, however. What it will likely bring is lower dew points, and not lower temperatures.

Sunday night and beyond, center of ridge doesn`t really move a lot early next week, and 925 mb temperatures don`t change much for at least Monday and Tuesday,  so a persistence forecast really looks to work well. Some divergence in solutions between the GFS and ECMWF operational solutions beyond that point regarding the center of the ridge with the ECMWF much closer to the local area. Would note, however, that even the GFS forecast soundings support next Thursday potentially being similar to, or potentially even warmer than this coming Saturday with 925 mb temperatures near 30C. That would support 100 degrees F, even on the south shore. Won`t go that warm, yet. No organized thunderstorms expected for much of next week.