Exceptionally dry stretch leads to a Flash Drought across the south

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ROANOKE, Va The latest U.S. Drought Monitor issued Thursday (Sep. 26) indicated the continued deteriorating conditions across the state in terms of drought.

The surplus of rain that the region experienced from the Spring of 2018 to the Spring of 2019 is now long gone. Short-term dryness and extreme heat have overcome any leftover wet conditions we had.

The rapid nature of this lack of rain and unusual late-season heat have led to the development of what's being referred to as a "flash drought."

Essentially, what would typically take many months to get this dry, has been expedited due to the combination of the heat and below average rainfall.

In Virginia, the latest Drought Monitor shows 54% of the Commonwealth is now in a "Moderate Drought."

A "Severe Drought" has developed across several southern states where water restrictions and shortages are already taking place. Fortunately, we aren't quite there yet, but we're headed in that direction if we don't get water soon.

Many counties and cities have issued burn bans, limiting or prohibiting open burning because fires will spread more rapidly. This comes ahead of the fall foliage season which can add even more fuel to any existing fires.

THE SUMMER HEAT

This has no doubt been the Summer of extreme heat. As of September 27th, Roanoke (and other areas) have recorded 60 days of 90º+ high temperatures. This puts us in 7th place in recorded history in terms of number of 90s in a single year. To get any higher in the ranking we'd need to get 5 or 6 more 90º days, which might be pushing it given the pattern shift coming soon. We are currently ranked as the 2nd hottest year on record.

THE LACK OF RAIN
We started off 2018 strong with a wet early Spring and even a surplus in June. It's almost as if the faucet turned off in July. As El Nino began to fade even more, the area was left with a rain deficit of 0.66" in August, and now 2.62" below average in September. Compare this to September 2018, when we had 9.92" of rain to end the month. Complete opposite.

Average rainfall per year for the Roanoke Valley is around 41.2". So far, Roanoke has had only 31.50" to date (Sep. 27). This means, we would need around another 10" to reach the yearly average. With three more months left in 2019, that's possible, ONLY if we get a pattern shift that brings something more than isolated to scattered showers. Anything less than a long-duration, steady rain event simply runs off due to the dry ground.

HOW DOES THIS COMPARE TO OTHER DROUGHTS?

The one thing about droughts is they typically don't occur rapidly; rather over many months or even years. This one has been the exception.

The area has experienced several equally dry stretches in recent years, but they have been in the winter, when water consumption isn't as high and evaporation isn't quite as extreme as the hot summer months. The last time we had a moderate drought in the summer months was in mid-Summer of 2012. That wasn't known to be one of the worst droughts, but lasted into the following winter until conditions improved some.

The worst drought years in recent memory were in 2001-2002, which nearly drained Carvins Cove and other reservoirs, and in 1998-1999.

Interestingly, during 2001, there was only 24.94" of rain that fell that year. We aren't even close to being that critical, but if we continue down this road into the winter months, it could come close to some of the other drought years where wells go dry, creeks are empty and animals come closer to our yards in a desperate search for food.

Just as we became dry, we can quickly see a pattern shift that can bring flooding, or even snow in the winter that can take us on the flip side. Time will only tell.