...EXTREMELY DANGEROUS HEAT WAVE OVER ALABAMA NEXT 3 DAYS...
This is the real deal. The heat wave we are forecasting today through Sunday is particularly serious, with high temperatures possibly nearing all-time record levels in some spots, and heat index values possibly 110 to 115 degrees. The ground is very dry, so almost all of the solar energy coming in during the day goes into heating the ground and the air, with almost none of it going into evaporating moisture. The sun is still near its peak height in the sky (we are only ten days away from the solstice), so days are long and the sun is very direct. A lot more sun energy is coming in every day than the ground can radiate back out at night, so each day until the air mass changes and we start getting scattered storms (early next week), it will get hotter. There is also no flow out of the Gulf to cool us off, with our low-level winds coming from the west.
All major computer models (NAM, GFS, GEM, and Euro) are forecasting temperatures between 100 and 108 over Alabama.
According to the GFS model (shown in graph), we'll reach 102 tomorrow, and 106 Saturday and Sunday. Temperatures will stay above 90 for 9 hours tomorrow, and almost 12 hours each day over the weekend. Humidity levels may start to increase some by this weekend, causing the heat index to soar to near 110. You would think with temperatures this hot and an increase in humidity that we would see scattered thunderstorms. However, the mid levels of the atmosphere are very warm too, so any storms this weekend will be isolated, and there may not be many clouds at all. Fortunately, humidity will increase further in the atmosphere by next week, allowing more clouds and scattered afternoon storms to cool things off.
This is a dangerous heat situation, and if you are planning to be outside, especially working, take frequent breaks, pour water on yourself, and drink plenty of water and Gatorade (all water and no electrolytes can be bad for you). A person can sweat as much as a quart every hour if doing work in this kind of heat, and sweat a lot just being outside. If you start to feel sick, go into the air conditioning immediately.
Right next to the ground it is 2-4 degrees hotter than the official temperature, so your pets are even hotter. If at all possible, they need to come inside during the heat of the day. Make sure they have plenty of water that sits in the shade and is refilled often (I use a big 5 gallon bucket for our beagle Jack, who is about to come in for a few hours now), and they need shady areas. Also, remember the elderly, as many of them may live in old homes with no air conditioning. Check on them regularly, because they may think they can tough it out, but this heat is dangerous. A box fan won't cut it this time.
Anyone without air conditioning needs to find somewhere to go that has it...friends or family's homes, public buildings, etc. Time spent outdoors should be extremely limited or avoided between 10 am and 5 pm.
Dr. Tim Coleman