JUNE COLD FRONT...WEEKEND STORM CHANCE

FORECAST DISCUSSION:

Good Wednesday afternoon everybody…I hope you all are doing well. Another typical warm and muggy June day in progress across the area with temperatures in the upper 80s and lower 90s…high dew points making it feel more like it’s in the upper 90s to near 100°F…sea breeze moving up into the Austin Metro Area as of 4:53 pm CDT will likely kick off a tiny shower or two as it moves through the metro area within the next hour…heaviest sea breeze activity is confined to our southeast across Fayette County where a fairly heavy downpour with some lightning and sub-severe gusty winds has developed. The rain chance at any one location this evening is 20%, dropping below 10% after 7 pm as we begin to lose the heat of day. Additional sea breeze showers and thundershowers possible again on Thursday.

Radar Snapshot (Wednesday, 4:49 pm CDT)…thin green line = sea breeze boundary…yellows/reds = heavy downpours

Pattern Shift

Pattern shift sets up across the lower 48 as we head into the next couple of days with a large ridge of high pressure setting up to our west and a deep trough of low pressure setting up to our east. That upper level wind configuration will create northerly winds aloft over Texas which will help to pull a rare June cool front into the area on Saturday…the front will bring a SLIGHT, did I mention slight, drop in temperature/humidity for the second half of the weekend, but more importantly, this front will provide sufficient lift as it moves into the area to generate some potentially heavy showers and thunderstorms across the area during the day Saturday into early Sunday morning. Storms that develop will have the potential to produce locally heavy downpours, deadly cloud to ground lightning, and gusty winds. Right now, I’m putting storm chances at 50% for Saturday and 30% for Sunday. The majority of the storms that develop Sunday into early next week should be confined to areas generally SOUTH of the Austin Metro Area as that is where the cool front will stall out and ultimately fizzle.

Forecast 500 MB (18,500 feet above ground level) wind flow across North America early Sunday morning…large ridge out west, deep trough out east…pink arrows = upper level wind flow

Meteorologists pay very close attention to upper level atmospheric dynamics because they ultimately create/steer surface weather systems (pardon the advanced image below and focus on the big H over the west, the big L over the great lakes and the pink arrows)

This weather pattern will be bringing well above normal temperatures to the western U.S. with below normal temperatures expected from the central into the eastern U.S. (This image shows temperature forecast for June 30^th through July 4^th)

Massive ridge of high pressure will be bringing record-breaking heat to portions of northern California and the Pacific Northwest…check out some of these forecasts for select cities in those areas over the coming days (forecasts courtesy of the National Weather Service)

Portland, OR

Medford, OR

Redding, CA

Forecast Rainfall Accumulation/Lightning Safety

Pinpointing how much rain we see across the area, I’m thinking a fairly scattered 0.25 to 0.50 inches of rain possible across much of the region with locally higher totals exceeding an inch or two inches possible as the atmosphere will be plenty juicy. We will have to be on the lookout for any slow-moving storms along the front, as they may pose a flash flooding risk. Overall, I’m going to be more concerned with folks outdoors and the potential for deadly lightning. Remember, if you can hear thunder, go indoors…it does NOT have to be cloudy or raining over your location for lightning to strike…it is a FACT that lightning can strike some 5-20 miles away from a parent thunderstorm…those bolts are commonly referred to as “bolts from the blue” and tend to produce the majority of lightning fatalities.

“Bolt from the Blue” Image: (Image Attached)

Photo courtesy of Ace Flint Hills’ photographer Jim Saueressig II