Now that August is here, it’s time to give an updated outlook for fall and winter for the Southeast.  In the short term, for at least the next few weeks, it seems likely that that fairly warm and wet conditions are likely to continue through the region. This means that daily pop-up thunderstorms will continue to show up around the region on a frequent basis, although they may not appear at the same places each day. This will continue to cause problems for farmers who are trying to do field work or who are being affected by fungal diseases and pests that like moist conditions. It will also continue to cause problems for those trying to make hay or who need dry weather for harvesting, although since fall is normally the driest time of the year, conditions should improve in a month or two if not sooner. Clouds associated with the moist conditions may make it hard to view the eclipse on August 21, although breaks could give some glimpses even if there are showers in the area.

NOAA and other forecasters have indicated that this year the Atlantic tropical season is likely to be active, and in fact we are running ahead of normal for the year, with TS Gert forming off the East Coast, although it is moving away from land and won’t affect us. The next storm, potential storm Harvey, has just come off the coast of Africa and has a 40% chance of developing in the next five days. It has a long way to go before it gets near the Southeast, so we have time to watch it. Even though we expect an active season, we don’t know where the storms will go because there are too many short-term atmospheric patterns involved in determining their paths. If a tropical storm or hurricane comes near your location you can expect windy conditions and heavy rain, but if you are farther away from the center of the storm you might get clear and sunny skies instead as air outside the storm circulation sinks and warms. The wet conditions this year have made trees weakened from drought in previous years especially susceptible to getting blown over, so if you have tree hazards on your properties, it might be wise to get them taken care of before a tropical storm gets close.

We are now past the spring predictability barrier for El Niño and La Niña, so we now have a pretty good idea of what ENSO conditions will be like this winter. The highest probability (55% or better) is that we will continue to be in neutral conditions through fall and winter, with some probability of La Niña conditions (up to 30%) and a small probability (no more than 15%) of El Niño conditions occurring in the winter months. Unfortunately, neutral conditions don’t give us much clue about what to expect for the winter, since other factors like sea surface temperatures in the Pacific and Atlantic Oceans have more impact in how the atmospheric weather patterns set up in neutral years.  We do know that neutral winters tend to have more ups and downs in temperature, so that you can probably expect more cold and warm spells than in the past couple of years. This could lead to higher chill hours accumulations, which would be great for peach and blueberry producers.  However, we also know that because of the larger variability there is a greater chance of a late frost in neutral years, which is bad news for those fruit farmers already hammered by the last two years of warm winters and the mid-March frost this year, although a late frost does not happen in every ENSO-neutral spring.

Throughout the next 12 months, there is an increased chance of above-normal temperatures compared to the 1981-2010 average conditions. This is due to the long-term trends towards warmer temperatures that are present in the observations, and is a continuation of what we have seen this year, with most months clocking in above normal, although of course there is some variation from month to month as the weather patterns change.

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