So, this past weekend, we had something that we had not seen around here in the Carolinas for many months: a round of good, old-fashioned rain. But did it improve any of the drought maps here in the Carolinas? We’ve got State Climatologist Corey Davis here. Corey, like we were talking about last week, a nice inch, two inches of rain in several areas. But what was the impact of this rain, and did it get us out of any of those droughts?
“Well, Kyle, we had high hopes for this event. We talked last week about the setup. There was a low-pressure system that tracked across the Carolinas, and the forecasts, at least, were showing some pretty good chances of an inch or more across North and South Carolina last weekend. For the most part, those totals did come through, especially across the central part of North Carolina. Most areas saw around an inch and a half. As we got further east, some of those totals were a little bit lower — only around half an inch for parts of the coastal plain in North Carolina and the Lowcountry of South Carolina. So those areas certainly would have liked to see a little bit more rain this past weekend.
“But again, a pretty widespread event. In fact, for places like Charlotte, that was the biggest rain event since September. So that really goes to show how long it had been since we had a nice rain. But you asked about the drought status, and there’s really not much of a change this week. South Carolina has actually stayed the same — still mostly severe drought across South Carolina now. And in North Carolina, there were no improvements. Actually, we saw some degradations. We mentioned some of those coastal areas that had the lower rainfall totals, and now we’ve seen extreme drought conditions emerge in places like Tarboro going up toward the Virginia border. So not the impact that we would have expected or hoped to see on the drought map. But again, that just goes to show how dry it’s been for so long now — six months into this dry spell.”
Now we’ve been talking about the drought map almost every week. And one question I have is, over at the State Climatologist’s Office, what drives the drought designation? What has to happen for an area — we’ll say Raleigh — to go from no drought to even moderate or severe drought?
“Yeah, one of my favorite sayings is that drought is not just skin deep. I know a lot of folks are probably noticing, after the snowmelt and after this recent rainfall, there’s some standing water and puddles in spots. Your yard is probably a little bit squishy right now. But really, that only tells us those surface-level conditions. We have been dry for so long — again, six months now — that we have seen this dryness start to get more entrenched. It’s not just those surface soils that are wet, but deeper down we see a lot of dryness, say one to two feet deep. And of course, for the farmers, that will really matter as some of those crops go in the ground this spring and start to take root. They will want to see some improvements in those subsoil moisture conditions.
“We also look at things like streamflow levels. After the rain event this past weekend, we did see a nice boost in those stream flows, but they’re already on the way back down, pretty much to those same low levels that they had before. We also look at lake levels. Now, fortunately, this time of the year, we don’t see the water demands or the evaporation rates that we do, say, during the summer months. But a lot of the lakes and reservoirs across North and South Carolina are still just struggling to hold steady. Their inflows are very low, and again, part of that is driven by the low stream levels. They’re really struggling to hold on to a sufficient amount of water for this time of the year.
“I know often we’ll look at ag impacts as well, but this is a time of the year when it’s hard to find a lot of agricultural impacts. It’s still a couple of months away from the start of the growing season. There’s not a lot of crops in the ground right now. But what we do know is that the farmers who have had their winter crops and their pastures growing this winter have really struggled with moisture conditions. So, putting all that together, that’s how we see this drought, even after we’ve had some recent rainfall, and why it’s really not improving just yet.”
So, you talked about stream levels and lake levels — a little follow-up. How important are those to the determination of a drought status for a region?
“Yeah, that’s one of the big drivers, especially across eastern North Carolina. You know, we saw that big foot-plus snow event a few weeks ago. We had hoped that as some of that snow melted, it would eventually infiltrate into the ground and also run off into some of the streams. But what we’ve consistently seen over the last couple of weeks is that along parts of the Cape Fear, the Neuse and the Tar River basins, those stream levels have just not seen the sort of boost we expected. So that’s one of the reasons why we haven’t been able to make improvements in those areas, even as they were getting some more moisture a little bit higher up into the soil column.
“One other note this past week is that parts of the Piedmont did see a small boost in those stream levels. But again, it’s just not sustained. So that’s one thing we’ll be looking at to make some improvements on the map — seeing those sustained boosts in moisture levels.”
All right, but what needs to improve overall here in the Carolinas to start to get a lot of these regions’ improvement on the drought map?
“I’d say the event that we had last weekend and the event that’s in the forecast for this weekend are really good starts there. It’s mainly just getting consistent rainfall in that one- to two-inch range week after week. Just for some perspective, some of the driest areas in eastern North Carolina, like Tarboro, are more than 10 inches below normal over the past six months. So, an inch or two a week will just slowly chip away at those deficits, but we won’t get rid of those deficits all at once. So really, that’s going to be the story and the goal over the next few months, as we head into the spring and the start of the growing season, is just getting enough rain to chip away at those deficits, to finally replenish those soils and the soil moisture from the top down, and also helping to top off those stream levels and those reservoirs so that we’re not looking at widespread water shortages or water restrictions as we head into the summer.”
All right, well, you teased a little bit about it earlier, talking about a potential rain event this weekend. What is the forecast looking like, as far as the potential rain event and also what’s going to come afterward — a possible drop in temperatures?
“Yeah, very active next few days. From today all the way through Monday, we’ve already seen some showers out there over the last couple of days. But really, that hasn’t inhibited our temperatures. We were in the low 70s yesterday. It looks like maybe some mid- to upper 70s across eastern North Carolina and South Carolina this afternoon. That will make it the warmest day of the year so far across a good chunk of the Carolinas.
“The better rain chances will start to move in by Saturday, and especially overnight into Sunday and then during the day on Sunday. There will be another low-pressure system that’s moving across the Carolinas, similar to what we had last weekend. In this case, it looks like some of the inland areas may not see quite as much rain — maybe only a quarter- to half-inch in those areas. But the coastal areas stand to see a little bit more. This time around, they could see upward of an inch.
“There is still some uncertainty about how this system may evolve. As that low moves off the coastline, it may start to intensify — sort of a classic nor’easter-type setup — and that may bring a little bit more precipitation in some of those coastal spots. But after that, Kyle, you mentioned a big change in our temperatures for the first part of next week. We’ll go from the 60s on Saturday to the 50s on Sunday, down to the 40s on Monday. So just a reminder: We’re not quite out of the winter just yet. Not looking at frozen precipitation this time around, but certainly a brief chill to start the next week.”
So, you say I’ve got to go back in the attic and get my winter stuff back out again.
“I think so. And looking at the nighttime lows as well, nothing hugely chilling, but at least some nights down to or a little bit below freezing. So, if you’re going to be outside in the early morning hours, yeah, you’ll probably need the toboggan. You may need that coat as well.”