- 7:38 am Tuesday, April 17th, 2018 by Kirk Mellish
Many things go into if there will be thunderstorms or how widespread they will be and how strong they will be.
There are different types of thunderstorms. I won’t go over all that now but have covered that in past blogs and will no doubt do so at some point in the future.
This is a simplified explanation of what goes into SEVERE THUNDERSTORM and particularly TORNADO potential. A severe storm is defined as one that can cause damage through wind or hail. (lightning can and does do damage and kill, but all thunderstorms by definition have lightning even weak ones not [More]
- 12:31 pm Sunday, April 15th, 2018 by Kirk Mellish
The threat of severe weather has ended for Metro Atlanta and scattered showers and thundershowers will be ending, but temperatures will slowly fall this afternoon behind the cold front.
A touch of snow may even mix with rain overnight in the higher elevations of the Northeast Georgia mountains.
Clearing for Monday but temperatures will struggle to reach 60 with lows in the upper 30s to low 40s the next couple nights.
LATE SUNDAY SURFACE WEATHER MAP:
LATE SUNDAY NIGHT:
MONDAY SURFACE WEATHER CHART:
MONDAY AM LOW TEMPERATURES:
TUESDAY MORNING LOWS:
However, a quick rebound to highs in the 70s is due Tuesday into next Saturday, Wednesday may reach [More]
- 10:45 am Saturday, April 14th, 2018 by Kirk Mellish
As is typical of Spring “winter” storm systems this one will run the gamut from blizzard and ice storm North to flooding rain and some tornadoes South, a pattern that started yesterday and will continue through the weekend.
Most of us in Metro Atlanta stay dry during the daytime, but the chance of a shower or storm goes up before sunset, especially North and West suburbs.
The greatest risk of severe weather comes well after midnight through early Sunday morning. The risk level is currently a 1 on a scale of 1-5, (marginal) but COULD go up to level 2 in updates [More]
- 6:05 am Friday, April 13th, 2018 by Kirk Mellish
Warmer than normal temperatures continue Saturday (average is now 72) but noticeably cooler Sunday, and then Monday highs will struggle to reach 60 with lows in the upper 30s to low 40s Tuesday morning.
We need to monitor heavy rainfall potential (looks like an average of 1 inch, with isolated higher totals) and maybe some severe thunderstorms in the warm to chilly transition.
SATURDAY AFTERNOON SURFACE WEATHER CHART:
SUNDAY SURFACE WEATHER CHART:
SURFACE WEATHER CHART MONDAY MORNING:
ESTIMATED AVERAGE RAINFALL SATURDAY:
ESTIMATED AVERAGE RAIN AMOUNTS SATURDAY NIGHT:
ESTIMATED AVERAGE RAIN SUNDAY:
SEVERE WEATHER OUTLOOK LATE SATURDAY AFTERNOON/SATURDAY NIGHT:
SPC SUNDAY SEVERE WEATHER OUTLOOK:
Here is the forecast discussion from the [More]
- 8:50 am Tuesday, April 10th, 2018 by Kirk Mellish
A very PRELIMINARY outlook for the coming tropical cyclone season was issued last week by some of the pioneers in the field at Colorado State University.
It was incorrectly characterized by many in the news business as a prediction for a “bad” season or “another busy season”.
I would not describe the outlook that way number one, and secondly there are multiple sources that make forecasts not just one! There is no “Royal decree” on the matter.
What is more, the track record of outlooks issued this early is not good. However, the ones that are issued in the coming months show useful [More]
- 5:40 pm Wednesday, April 4th, 2018 by Kirk Mellish
I don’t have a vegetable garden but I will hold off planting any new sensitive bushes or flowers until around or after April 20th just to be safe given the topsy-turvy pattern that looks to continue.
If you read my blog regularly or follow me on Twitter you know this is just what I was worried would happen since mid-January, unfortunately that fear has been borne out.
Cold snaps and warm spells look to continue to trade back and forth.
At least one more and possibly two more nights with lows in the 30s before this month is done, especially away from the [More]
- 7:03 am Friday, March 30th, 2018 by Kirk Mellish
For months on Twitter and here in this blog I’ve been covering how warm spells would come but with periods of below-normal temperatures in-between.
So far most signals support this pattern continuing through at least the first week or two of April.
However, the signals are starting to become more mixed beyond that.
Its been a see-saw past 90 days:
This time of year the negative North Atlantic Oscillation (-NAO) is a primary driver for temperatures. It does not show signs of going positive anytime soon:
In the Spring a negative NAO will often allow for cool snaps even in the face of warm signals [More]
- 9:27 am Tuesday, March 27th, 2018 by Kirk Mellish
Big warm up still expected after the wedge. Opening Day for Baseball has big rain risk and possible lightning for the Atlanta Braves, but most of the rain comes in the evening Thursday.
We have to monitor the risk of a severe thunderstorm Thursday evening but right now does not look significant, but that could of course change.
THURSDAY SEVERE WEATHER OUTLOOK:
THURSDAY RAINFALL AMOUNT ESTIMATE:
It seems weird to have Easter on April Fools’ Day.
EASTER WEEKEND weather looks dry both days! Cool mornings, mild afternoons with more clouds Sunday than Saturday.
As they have for over a month now, the models suggest the see-saw [More]
- 7:03 am Friday, March 23rd, 2018 by Kirk Mellish
In the scientific literature it’s known as a CAD EVENT.
That’s Cold Air Damming.
It is known colloquially as “A wedge”, that’s the local nickname.
I’ve explained it on the radio and in my blogs dozens to hundreds of times before.
We call it the wedge, because a different air mass wedges against the mountains and into the metro area. The mountains act like a dam. Holding the air mass in place.
There are different types of wedges and they vary in strength and geographic extent. Sometimes they last for days, sometimes half a day. Sometimes they only impact the far Northeast suburbs, other [More]
- 6:20 am Tuesday, March 20th, 2018 by Kirk Mellish
The low pressure and frontal system that brought the stormy weather Monday night with scattered damage and power failures will turn into the 4th Nor’ Easter snowstorm and bring another bought of below-normal temperatures to Atlanta.
Some sleet and snow showers or flurries are even possible Wednesday in the high elevations of the Northeast Georgia mountains.
Surface weather chart late afternoon Tuesday:
Severe weather risk Tuesday:
Surface weather chart Wednesday Morning:
Wednesday Night surface weather chart:
FORECAST SNOWFALL ACCUMULATION:
GFS ENSEMBLE LOW TEMPERATURE FORECAST THURSDAY AM:
ECMWF Model Ensemble Temperature output:
Up and down active changeable weather pattern expected to continue through April as seen in the mean output [More]