Regional Weather Turns Active Thursday and Friday: Strong Storms and Heavy Rain Possible
The weather pattern across North Carolina is getting ready to become considerably more active as we head toward the end of the workweek.
Thursday will bring another hot afternoon across much of the Piedmont, but attention will quickly turn toward developing thunderstorms. By Friday, a moisture-rich atmosphere and an approaching weather system will bring a much greater chance for widespread showers and thunderstorms across the region.
For Rowan County and surrounding areas, Thursday will be the beginning of the transition, while Friday currently appears to be the wetter and potentially more impactful day.
Thursday: Strong Storm Potential Increases
The Storm Prediction Center has outlined a large portion of North Carolina in a risk for thunderstorms Thursday.
Much of the Piedmont, including Rowan, Davie and Davidson counties, is within a Level 1 of 5 Marginal Risk for severe thunderstorms.
A Level 2 of 5 Slight Risk is mainly confined to the northeastern corner of North Carolina, extending into portions of southeastern Virginia and the Mid-Atlantic.
For our regional coverage area, the primary concern will be the possibility of an isolated severe thunderstorm capable of producing damaging wind gusts.
The damaging-wind probability outlook shows a broad 5% risk extending across much of the Piedmont, including our area. Higher probabilities are concentrated well to our northeast.
Thursday will also be another hot day before thunderstorms begin developing.
For Rowan County, the forecast high is near 93°. Davie County is expected to reach around 92°, while Davidson County reaches approximately 93°.
When Could Thursday's Storms Develop?
Thunderstorms could begin developing Thursday afternoon as an approaching cold front interacts with the hot and increasingly humid air across the region.
For Rowan, Davie and Davidson counties, this remains a Level 1 Marginal Risk, meaning severe storms are expected to be isolated rather than widespread.
The more concentrated severe-weather threat is currently expected well northeast of our area, particularly across northeastern North Carolina and into southeastern Virginia.
Even within a Marginal Risk, however, it only takes one severe thunderstorm to produce damaging winds in a community.
Storm timing and coverage will continue to be refined as newer guidance gets a better look at Thursday's environment.
Thursday Night: Rain Chances Increase
For our immediate region, shower and thunderstorm chances become more noticeable Thursday night.
Current probabilities include:
Rowan County: 40%
Davie County: 50%
Davidson County: 40%
Some locations may receive locally heavier rainfall underneath thunderstorms.
Thursday night's activity will also help set the stage for what could become a considerably wetter Friday.
Friday: Widespread Rain and Thunderstorms Become the Main Story
By Friday, the emphasis begins shifting away from Thursday's more traditional severe-weather setup and toward a combination of widespread thunderstorms, heavy rainfall and localized flooding potential.
A very moist air mass will be in place across North Carolina.
Forecast guidance indicates atmospheric moisture will be abundant, giving thunderstorms the ability to produce very efficient rainfall.
Showers and thunderstorms should become increasingly widespread during Friday afternoon and continue into Friday night.
Current rain chances are:
Rowan County: 60% Friday, increasing to 90% Friday night
Davie County: 60% Friday, increasing to 90% Friday night
Davidson County: 80% Friday, increasing to 90% Friday night
Friday evening and Friday night currently appear to be particularly important periods to watch.
Friday's Severe Weather Risk
The Storm Prediction Center's Day 3 outlook places a broad portion of North Carolina, including much of the Piedmont, within a General Thunderstorm Risk for Friday.
A Level 1 of 5 Marginal Risk is currently focused primarily across southeastern North Carolina and portions of the Coastal Plain.
That means Rowan, Davie and Davidson counties are not currently included in an organized severe-weather risk for Friday.
However, that does not eliminate the possibility of stronger thunderstorms.
The environment may contain enough instability and wind shear for some storms to become better organized. Strong to damaging wind gusts could occur with the strongest thunderstorms, particularly where heavy precipitation creates powerful rain-cooled downdrafts.
The Friday outlook can still change as additional forecast data becomes available.
Heavy Rain Could Become Friday's Bigger Concern
While severe weather will need to be monitored, heavy rainfall may become one of Friday's more widespread concerns.
Forecast rainfall guidance shows a broad area of precipitation developing across the Carolinas and Mid-Atlantic through Friday night.
Across much of the western and central Piedmont, current guidance generally suggests totals on the order of several tenths of an inch, although thunderstorms can produce considerably higher amounts on a localized basis.
The greatest widespread rainfall totals are currently projected farther east and southeast, where amounts exceeding an inch become more common in the guidance.
But don't focus too heavily on one exact rainfall number.
Thunderstorms can create dramatic differences over short distances. One community could receive relatively little rain while another nearby location gets hit by multiple thunderstorms.
The bigger concern Friday will be the potential for very heavy rainfall rates.
If thunderstorms repeatedly move across the same locations, rainfall totals could quickly climb.
That could result in flooding of poor-drainage areas, low-lying locations, urban streets and small creeks or streams.
Never attempt to drive through a flooded roadway.
Friday Night Could Be Particularly Wet
The current forecast deserves some attention for Friday night.
Rowan, Davie and Davidson counties all currently carry a 90% probability of precipitation.
Davidson County's forecast currently calls for an additional one-half to three-quarters of an inch Friday night alone.
The placement of the heaviest rainfall will ultimately depend on where thunderstorms develop and whether storms repeatedly track across the same areas.
Because of that, rainfall totals could vary substantially over relatively short distances.
What Happens After Friday?
Showers and thunderstorms could linger into Saturday as the cold front slowly works through the region.
The exact timing of the front remains uncertain, which will determine how widespread Saturday's storms become.
The good news comes behind it.
Drier air should begin filtering into the region by Sunday, bringing lower humidity, reduced rain chances and temperatures returning to the middle and upper 80s.
Sunday and Monday currently look considerably more comfortable than the hot and humid weather we've experienced this week.
The Bottom Line
There are two different weather periods to watch as we approach the end of the week.
Thursday: Another hot day with thunderstorms becoming possible during the afternoon and evening. Rowan, Davie and Davidson counties are in a Level 1 Marginal Risk, with isolated damaging wind gusts the primary severe-weather concern. The Level 2 Slight Risk is mainly confined to northeastern North Carolina, well northeast of our immediate coverage area.
Friday: A much wetter pattern develops with widespread showers and thunderstorms possible. Heavy rainfall and localized flooding become increasingly important concerns. Some thunderstorms could also produce strong wind gusts, although our immediate area is not currently included in an organized severe-weather risk for Friday.
For Rowan County and the surrounding region, Friday afternoon through Friday night currently appears to be the period with the greatest potential for widespread impacts.
There is still time for the forecast to evolve, particularly regarding storm timing, rainfall placement and the location of any stronger thunderstorms.
I'll continue monitoring the latest information and provide updates as Thursday and Friday's weather comes into better focus.