FIRST DAY OF AUTUMN TODAY – BIG CHANGES ON THE HORIZON

UPDATE: The forecast below is largely unchanged. For this update though, the frontal timing will be adjusted a bit to reflect the latest data. The front is now expected to move across the DFW Metroplex on Sunday in the late morning to early afternoon timeframe as opposed to Sunday night. We are still expecting a decent rain event into early next week, with rain chances now extending into Tuesday. There should be widespread totals by Monday of 1 to 3 inches of rain with locally higher amounts possible.

Although today is the autumnal equinox, it will still feel like summer with above normal temperatures with highs well into the 90s continuing today. Though, we should thankfully not see any more triple digit heat like earlier this week. However, there are some big changes coming our way.

  • Moisture will begin to increase tonight in response to storm system forming out west.
  • Showers and thunderstorms will be on the increase tomorrow, mostly along and south of I-20, in response to the storm system moving out of the Rockies onto the Plains.
  • Showers and thunderstorms become more widespread on Saturday through Sunday.
  • PWATs increase to 2+ standard deviations above normal, setting the stage for bouts of heavy rain Saturday night through Sunday.
  • Strong cold front expected to arrive Sunday night (though timing could change). This will be the first significant cold front of the fall season.
  • Discrepancies between the ECMWF and GFS models, with the former cutting off energy and hanging it back, dictate when precipitation will shut off, regardless substantially drier and much cooler air will move in behind the cold front. Rain may linger into Monday per ECMWF which may effect degree of cooling of temperatures.
  • Widespread 1 to 3 inches of rain expected by Monday with locally higher amounts possible.
  • Temperatures behind the front should cool to the 50s in many areas for the first time this season with highs in the 70s.

The forecast could obviously change given the discrepancies among the ECMWF and GFS, especially with ending of rain and amount of cooling of the temperatures behind the front. Overall, the theme of a wet weekend and much cooler weather early next week is looking likely no matter which solution verifies.