A Tale of Two Droughts

There’s a bad kind of drought and a good kind of drought in our state right now. There’s also some good news about both to share tonight. The first is the drought in the traditional sense – the extreme lack of rainfall over the past half-year in the western half of Oklahoma. The other is the extreme lack of severe weather, specifically, tornadoes, in our area as well. Here’s more about both and why they are related to one another.

                The rainfall drought has plagued western Oklahoma since last summer. The past 6 months have been especially brutal for the Panhandle and far western reaches of the state. Some places saw less than an inch of rain over that entire time. In fact, up until yesterday, Kenton, Oklahoma, at the western tip of the Panhandle, had gone 203 days without a quarter inch of rain or more on any given day. That adds up to a paltry 0.68” over that stretch. In the past two days, they’ve nearly doubled that rain total. Below, you’ll find the state of the drought from earlier this week with the weekend rain totals so far placed beneath that. Rain really did fall where it was needed. That’s the good news.

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                The bad news is that it’s still just a drop in the bucket compared to what is needed to eradicate a drought, especially one in the worst category. We’ll need an incredibly wet spring with consistent heavy rainfall for the next few months to really put it to bed.

                The good kind of drought, as I mentioned earlier, is the lack of tornadoes we’ve seen in Oklahoma. Below, you’ll see some of the statistics on our “tornado drought.” While a few have been close to the Oklahoma state line, none have touched down in the state since last October. We are fast approaching that “latest first tornado” date and just 5 days shy of the all-time longest streak without a tornado.

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                Why is this the case? Much of it has to do with our other drought. A lack of available moisture from the drought-stricken areas has reduced one of the key components to tornado formation for one. By the time storms would form and reach maturity when they could produce tornadoes, they have been just south or east of the state. That is common early in spring, but by this point in April, we are typically ground zero for tornado activity. Each year is different and so far the jet stream pattern has also kept storm systems from taking a favorable track with favorable timing for tornadic storms. This weekend’s beneficial rainfall came without severe weather simply because the storm system took a more southerly path, putting us on the cool, stable side of the system. The unseasonably cool month of April, thanks to a persistent trough in the jet stream over the central and eastern U.S., has also kept late winter conditions in place far longer than normal.

                So where do we go from here? In terms of our recent rainfall and continued shower activity into Sunday, we are getting a nice respite from the wildfires that have burnt hundreds of thousands of acres across Oklahoma. While one soaking rainfall doesn’t keep wildfires from flaring up for long, it will help to green up the parched ground out west and limit any fire spread state-wide with the added moisture. This is a slow-moving system that will pull the jet stream south behind it. This “Northwesterly Flow” pattern rarely favors too much severe weather this time of year because each fast-moving wave diving our direction won’t be able to pick up much moisture before it arrives. Essentially, this is the same weather pattern we’ve seen all April. Therefore, the week ahead looks extremely benign for what is usually one of the most active time periods for severe storms.

                In about a week, a deeper, stronger storm system will push across the country. It’s yet to be seen if this will have the available moisture or instability to do much for us, but it could be the start of a more active period heading into early May. While there isn’t one main storm system really grabbing my attention in the extended outlook, it does appear wetter and more active as the final map shows below. By that point, these unseasonable cool spells should be a thing of the past and it’s more likely ingredients will be there to end our tornado-free streak. If I were a betting man, I would certainly place my wager on breaking the former record of 187 days without a tornado.  The week ahead just doesn’t have much potential. As meteorologists, we are definitely grateful, but still on guard given the normal volatility of this time of year.

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                The quiet and cool start to spring doesn’t mean that the rest of our storm season will be quiet. If we see a different jet stream pattern get locked into place, we could make up for lost time in May, the heart of our tornado season. At least if that’s the case, we’d be probably reducing the drought out west in the process. However, continued dry weather out west could also mean for a more eastward-set dry line, which could put Green Country in line for some large and destructive storms that often affect central Oklahoma more often.

                Here’s hoping we can make it unscathed through the next month and a half. If we can reduce the main drought while keeping the tornado drought alive and well, we’d be oh-so fortunate. For more on our latest weather, be sure to follow me on Twitter: @GroganontheGO and on my Facebook Page!