Posted: 8:07 am Wednesday, July 26th, 2017
By Kirk Mellish
Our latest “mini heat wave” is near its zenith with hot and muggy summer weather today and tomorrow with only a small handful of hit or miss end of day pop up storms. Highs 90-94 and lows 70-75. The mid day Heat Index or “feels like factor” topping out around 98 each day in the shade.
But changes are on the way that will bring more comfortable weather with less heat and a little less humidity on the weekend, especially noticeable by Sunday into the first half of next week!
In the transition the risk of severe weather will go up: first in the mountains late tomorrow then the rest of North and Central Georgia Friday.
Saturday the best chance of a thunderstorm will be from around I-20 southward. The refreshing air mass change could mean some morning low temperatures down to near 60 Sunday or Monday morning in parts of North Georgia as a continental air mass replaces the tropical air mass we have now.
While the rain chance Saturday is too low to worry about, I’ll even take it out of the forecast entirely Sunday and Monday with relatively dry air for summer. That is certainly an anomaly for this time of year in Atlanta.
More typical summer weather will return the second half of next week and beyond, nothing extreme though.
You can see in the series of weather charts below how the change in the upper level jet stream height pattern flow brings the changes to the surface weather:
500mb jet stream pattern WEDNESDAY:
500mb jet stream pattern SUNDAY:
TEMP ANOMALIES NEXT 48-72 HOURS:
TEMPERATURE ANOMALIES BY SUNDAY:
WEDNESDAY AM SURFACE WEATHER CHART:
SATURDAY AM SURFACE WEATHER CHART:
SEVERE WEATHER RISK THURSDAY:
SEVERE WEATHER OUTLOOK FRIDAY:
3-DAY ESTIMATED RAINFALL AMOUNTS ON AVERAGE:
MODEL ENSEMBLE TEMPERATURE TRENDS: