Severe Threat Thursday

A front will arrive in our area tomorrow evening and bring us a good chance for thunderstorms. Thunderstorms will start popping west of I-95 between 5 and 8 PM. Scattered thunderstorms will then overspread central Virginia from 8 PM to 4 AM.


I think the computer forecasts are keeping our high temperatures too low. With partly cloudy skies for the first half of the day, we should easily climb into the upper 80s. That means our atmosphere will be more unstable than what is currently depicted by the computers.

Jet stream winds will be strong, so there will be plenty of speed shear. Winds will be southwesterly from the ground all the way into the upper atmosphere. This means that damaging winds will be the primary threat tomorrow. An isolated short-lived tornado could develop within the strongest storms, however, once the storms form into a squall line, the threat for tornadoes will decrease.

Some Changes Headed This Way

The North Atlantic Oscillation (NAO) is a great way to spot long term weather patterns. Whenever NAO is negative, temperatures will stay near or below normal - like in February and early March. Whenever NAO is neutral or positive, then the Mid-Atlantic will be generally warmer than normal - like late March and all of this month. All indications point to NAO diving back negative by the middle and end of this month. This mean that temps will return to near or below average to finish the month. It could also be the return of a stormy weather pattern. This is something we will be tracking over the next several days and will have more updates soon!

(Past and forecasted NAO)

It's Official!

The official high today was 93, so we broke the old record set back in 1942. Here's another toasty tidbit: it's been 194 days since we have seen temperatures in the 90s!

Unusual April Heat

As a broad area of high pressure remains over the entire Southeastern U.S. into the Mid-Atlantic, much-above-average temperatures continue in the region. On Monday, the high at Richmond International Airport was 89 degrees, which tied the record for April 5 from 1942. The record-to-beat on April 6 is 92 degrees, also from 1942. We should come very close to tying that record. This will also be the earliest 90-degree day in Richmond in recent years:

A strong cold front is expected to sweep through the East Thursday night, bringing a line of showers and thunderstorms and a return to cooler, more typical early-April temperatures at the end of this week.

Temperatures Continue To Climb

High pressure will settle to our southeast and create prime conditions for major warm-up. Here are two records we will be watching:

• Tuesday...92° set in 1942
• Wednesday...94° set in 1929

Although I don't expect us to break those records, we will get very close on Tuesday. I will throw one more significant date your way:

• Average last freeze...April 8th
  

Cooler air will head this way by next weekend, but we should still stay well above freezing during the night. It's possible that we have seen our last freeze of the season!

Sunshine, Shades, & Sunblock

Much of Central Virginia will likely have its first 80-degree day of the year today, with the high in Richmond expected to top out at 81 degrees. The warmest temperature so far this year at Richmond International Airport has been 79 degrees on March 20. We will also have full sunshine today and the rest of this week, with only occasional high, thin clouds. We are now into the full swing of Spring, which also means that more of the Sun's incident rays are more directly reaching us in Virginia. That means the UV Index is creeping higher, and some of you may have already had your first sunburn of the season. For Thursday, the UV Index is at 8, which is Very High. For your reference, here's the UV Index Scale from the Environmental Protection Agency:

Over the next week, be sure to protect yourself outdoors as you enjoy the warmer weather!