More Rain To Kick Off June

It looks like the rainy pattern that we have been in, is not going away anytime soon thanks to a near persistent trough of low pressure covering the eastern half of the nation. Although it will shift, and loose it’s grip on us from time to time, the overall result will lead to above normal rainfall and below normal temperatures. The following chart shows the 500 mb circulation around the northern hemisphere. The big L parked over the Great Lakes is the trough that is currently helping to bring us the unsettled weather of late.

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The forecast from the Climate Prediction Center points to this trend continuing as well. Both the 6-10 day, and 8-14 day forecasts call for below normal temperatures and above normal rainfall.

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The winner in all of this is the drought situation across north and central Georgia. Since the beginning of the year the percentage of the state that was under extreme drought has been reduced from 49.64% to 6.37% with absolutely zero extreme or exceptional drought showing up in north Georgia. February and March were not kind to us as far as rain is concerned. A combined 4.55″ in that stretch was woefully below normal. Since then we have made up ground with 5.75″ in April and 4.35″ so far this May!

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So even though it seems like we can’t get a break from the never ending showers and t-showers, it will be nice to be ahead of the game before the dog days of summer arrive.

BELOW NORMAL TEMPERATURES?

Yes that’s right we have below normal temperatures in the forecast for this week, but what about next? The 6-10 day forecast indicates some relief for areas to our west but here in north Georgia it appears that we will see temperatures at or near normal.610temp.new

So don’t get too excited about the prospects of August all of a sudden becoming cooler than normal here is north Georgia. Rainfall could be a different story. It looks like the unsettled, rainy pattern developing this week could continue into next week as well bringing much needed rain to our area.814prcp.new (4)

Above normal rainfall would be a beautiful thing since much of the central and northern part of the state is either in severe to extreme drought.

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MAY 23rd-27th OUTLOOK

Another big week on the way next week with plenty of graduation ceremonies, and the start of summer for the kids. So it would seem imperative that the weather cooperate, and lo and behold it looks like it will. Not only will the week be dry, but warm as well. In fact warm may be an understatement. Highs could be back into the mid to upper 80’s.

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In fact some of the warmest air so far this spring. As far as rain goes…..don’t see much of that happening at all barring a pop up shower or t-shower.

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As with all long range forecasts take them with a grain of salt, although this one appears to need a little less salt than some others in the past.

EL NINO AND THE SUMMER FORECAST

So will it be a hot summer? That is something we get asked all the time, so I thought  I would try to lend some insight to the issue. Keep in mind there are many factors that can and will influence the outcome of the Summer of 2016, but I though it would be fun to just look at it from an El Nino or lack thereof point of view.

First off I compared the El Nino of this past year with the one that occurred in 1997-1998. They are very similar in strength, in fact two of the strongest on record. Here is a table showing the strength of the El Nino as represented in red numbers for all the years since 1997.

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EL NINO TABLE PP

Both episodes 1997-1998 & 2015-2016 almost mirror each other except with the fact that the El Nino started two months earlier this go around. Assuming that all goes as planned this years El Nino should go neutral soon and then reverse into a La Nina pattern heading through the summer (blue numbers with negative values). This would correlate with the summer of 1998 which started to shift out of an El Nino in May.

So what was the summer of 1998 like here in Atlanta? Quite hot and dry except for August which turned out wetter and cooler than normal. So if we just went with the El Nino alone then one would assume that this summer should be hot and dry with more than our share of 90 degree days. In fact during the summer of 1998 there were 42 days during June, July and August where the high temperature was 90 degrees or better. The average is 37 days.

NEW 6-10 DAY OUTLOOK

With all the above normal temperatures that we have had lately anything close to normal will seem cool, and that is exactly what we have in store for the rest of this week. In fact by Thursday our high temperatures across north Georgia will only climb into the low to mid 60’s! Luckily warmer air and sunshine will return for the weekend with highs by Mother’s Day climbing back into the low 80’s.

Looking ahead to the following week it looks like near normal, or just slightly above normal temperatures can be expected here across the Southeast.

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Much of the West Coast will remain well above normal with cooler than normal temperatures expected from Texas to the Great Lakes.

Along with the warm weather that we have had recently it has also been very dry. That looks to change at least for next week. The 6-10 day precipitation forecast is calling for above normal rainfall in a large area from Texas to the Southeast north to the Ohio Valley.

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This would certainly help to alleviate the dry conditions across north Georgia that have developed in the recent months. In fact much of the area is classified as either abnormally dry or in moderate drought.

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FINALLY WARMING UP?

Finally there is a glimpse of warm Spring weather on the horizon. Warmer temperatures will arrive starting this weekend and should stay a while. There could be an occasional cool day, but the trend toward consistent warm weather will develop. The average high and low by the 20th is 74 and 53, so you would expect to start seeing more consistent warm weather. For this week highs will struggle to get above 60 both Wednesday and Thursday with overnight lows dropping into the 40’s! By next Monday and Tuesday highs could be near 80 with overnight lows in the 50’s! Quite a turnaround. Here is the 8-14 day temperature and precipitation outlook from the Climate Prediction Center and it to favors warm and dry weather through the 24th.

8-14 temp

Not only will we have above normal temperatures, but much of the nation will as well especially the West.

8-14 precip

As for rain much of the nation will be dry with the only above normal areas being along the Gulf Coast and Florida.

So if you have been waiting to plant the spring garden it looks like this weekend should be perfect!

SHOWERS & T-STORMS THURSDAY

A strong cold front will approach the Southeast late Wednesday and through the day on Thursday bringing with it showers and a few t-storms. The SPC has an area southwest of Atlanta under a slight risk for severe t-storms. The area in question would include all counties south of I-20 and west of I-75.

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If severe t-storms do occur the main threat would be from damaging winds. Lightning will also be a threat so be sure to seek shelter if a storm approaches. The best timing appears to be in the morning on Thursday and then again late Thursday night into early Friday morning.

Here is a look at two different computer models (GFS & NAM) that paint a slightly different story. The GFS model is more aggressive and faster then the NAM. Here is the GFS for 2 am Friday morning.

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If this is correct a fairly strong line of t-storms will be moving through much of North Georgia in the overnight hours into Friday morning. The NAM on the other hand shows far less activity.

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As for the timing the GFS has the rain moving out in the morning on Friday while the NAM keeps the shower activity around through Friday afternoon. Here is the GFS for 2 pm Friday clearly showing the showers well to the east and south.

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The NAM on the other hand keeps showers (although light & few) around through 2 pm on Friday.

wsi nam 18z

I’m leaning more toward the GFS with the faster solution. Once the system makes its way to the east look for another cold snap with lows down into the 40s and 30s both Saturday

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and Sunday morning.

sun am lows

APRIL: COOLER & WETTER

Don’t get too used to the warm spring weather of late, because a more active pattern will emerge for the end of March and the beginning of April. This will allow for slightly cooler than normal temperatures,
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and above normal precipitation.

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The outlook for the entire month of April is a little less clear, but I think a more active pattern will continue allowing for an overall cooler and wetter month for north Georgia. The official outlook has us in an equal chances category for temperatures,

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and above normal chances allowing for a wetter than normal month.
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The El Nino which has been raging for the past year is finally showing signs of weakening, so maybe this is the last gasp as we transition to an ENSO-neutral phase heading into summer.

WEEKEND WEATHER OUTLOOK

Reality will set in this weekend after a week that saw record high temperatures, and soaring pollen counts. Cold air combined with moisture from the Gulf of Mexico will interact to bring us a cold raw day on Saturday, but luckily the sun will return on Sunday although the cool weather will remain.

The good news is that lots of sunshine will be with us both Thursday and Friday before the clouds start to increase overnight Friday and into Saturday morning.

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This will be the beginning of a wedge event that will solidify itself through the day on Saturday. Overrunning moisture will start to produce light rain by mid-morning that could last for most of the day.

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There is a chance that we get by with just an overcast sky and very little rain on Saturday, but if the outcome is as advertised we could get a decent amount of rain. About a half inch seems to be the consensus as of now.

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Luckily by Sunday the storm system will be to our east and clearing will begin to take place from the west. Temperatures will still be on the chilly side, but at least the sun will return for the second half to the weekend.

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Last but not least Spring officially arrives Sunday morning at 12:30 am!

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WEEKEND WEATHER OUTLOOK

With the weekend fast approaching you’re probably wondering what we can expect across north Georgia. Earlier in the week it looked like late Friday through early Sunday would be the best time frame for showers and even a few t-showers. Now it looks like the upper level system over Texas is going to stall out, and take longer to reach the Southeast.

You can see from the hour-by-hour forecast that the rain hardly advances eastward through Friday. The only minor exception would be a few light sprinkles in the northeast Georgia mountains early Thursday, and a few showers in northwest Georgia early Friday morning.

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Saturday should turn out to be dry with the bulk of the rain arriving Sunday. The storm system will be responsible for huge amounts of rain up and down the Lower Mississippi River Valley with some spots seeing more than 6″ of rain between now and Saturday morning.

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By the time the storm arrives here there wont be much left of it. In fact across north Georgia don’t expect much more than a half inch of rain during the day on Sunday with little to no t-storm development.

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So once again if you have outdoor plans this weekend you’re set for Friday and Saturday, but not Sunday.