Out With The Old...

Over the past couple weeks, you have probably noticed our new Storm Center and weather graphics. Although things have improved significantly as we continue to modernize our TV station, I couldn't help but be somewhat sentimental as the engineers dismantled the old set. Here are some photos and video:

Heat Index This Weekend

As a strong ridge of high pressure remains over the eastern U.S. this weekend, highs will climb into the upper-80's and low-90's, as detailed in the previous blog entry. Winds will be from the southwest at the surface this weekend, allowing for the return of some moisture into the Commonwealth. Moisture and heat combine to produce the heat index value. This "temperature" is a value based on the air temperature and the dew point temperature. It measures what the temperature will feel like to your body when you are in the shade. Yes, in the SHADE. Not in the sun. When you're outdoors in the sunlight, you can tack on about another ten degrees on top of the heat index value for what it will feel like to your body. In addition, the higher the humidity, the harder it is for the human body to effectively cool the skin quickly by sweating. On Saturday in Central Virginia, the heat index will be around 90 degrees, but by Sunday, heat indices will rise into the mid-90's in the shade. Add ten degrees for standing in the sun, and you've got an apparent temperature of 100 degrees. That falls into the "Extreme Caution" category for high risk people (kids, the elderly, and anyone with chronic conditions). But anyone spending extended time outdoors can still experience these symptoms.

You can calculate your heat index here.
In addition to the heat index, as you enjoy the warm temperatures this weekend outdoors, remember the UV Index will be High to Very High.

Be safe and enjoy the warmth this weekend!

Summer-Like Warm-Up

A strong ridge of high pressure is building into the eastern U.S. starting today, and will influence our weather in Central Virginia through this weekend. Southwest flow will bring in milder air and plenty of sunshine beneath this high pressure, which will allow high temperatures to reach the 80's by Friday, and near 90 degrees by Sunday. Here is a view of the upper ridge by Saturday afternoon:

The record highs to beat are:

Saturday, May 1: 94 degrees (1942)

Sunday, May 2: 92 degrees (2007)

I think by Sunday, we may be very close to tying or breaking the record high! This stretch of summer-like heat will come to an end Monday, though, as the strong ridge weakens and slides southeast and a cold front begins tracking through the Commonwealth from the northwest. Ahead of this front on Sunday and Monday, showers and thunderstorms will be possible. Here is a view of the surface weather map by Monday evening:

The front will clear the state Monday night, bringing cooler temperatures with highs back in the 70's Tuesday into mid-week.

Full Fish Moon Tonight

Tonight's full moon has an interesting name: the fish moon. The Native American tribes of the coastal regions of the east coast gave it that name, because April is the month when shad swim upstream to spawn. What can I say, it's a quiet weather day.

Any Aches and Pains Yesterday?

You've probably heard more than one person "up in age" say they can tell when storms are coming by the pain they feel in their knee. Yesterday was one of those days when all of us could sense something was going on in central Virginia. The pressure dropped to 29.20" of mercury, which is the lowest it has been since January 7th of 2009 when the pressure fell to 29.19". My wife told me she could feel it in her ears, and my son who is normally very happy, was crying from an apparent ear ache. The time was about 7 PM, when a strong storm moved through the Richmond area. Most of the time our surface pressure ranges from 29.50" to 30.50", with strong areas of high and low pressure resulting in readings on either side of that range.

Race Doubleheader Forecast

Racing is back in Richmond this weekend with a doubleheader Friday and Saturday nights, both races starting at 7:30 PM. At this time, it looks like both days will be dry and warm (Friday's High: 79, Saturday's High: 84) as a strong ridge of high pressure will be in place from the Southeast to the Mid-Atlantic at the end of this week. Here's the upper-level map showing the ridge Friday evening:

But you can also clearly see the large low pressure system over the Plains at the end of this week, too. That's the system we expect to reach the East Coast by Sunday. However, if this system moves a little faster and the ridge weakens or shifts farther east, the rain may move into Central Virginia by Saturday afternoon. The timing of this system will be closely watched for its potential impacts on Saturday's Heath Calhoun 400. Check back here for updates on the forecast!

Weather Update - 4:00 PM

Clouds are starting to break apart across the region this afternoon, which will allow the sun to heat us up. The atmosphere is already unstable, so this will only add fuel to the fire. The upper-level storm system continues to churn to our west and will eventually bring enough "lift" to create a few thunderstorms this afternoon and evening. Storms will be widely scattered, so not everyone will see the rain. However, any storms that develop could quickly become severe, so we will be tracking this very closely over the next several hours. It looks like the threat for severe weather will quickly diminish after midnight tonight.

Severe Threat Sunday

Strong southwesterly winds will bring warm and humid air into our area.


This will increase instability in the atmosphere, which is measured by CAPE.

A strong jet max (area of strong winds) will move in during tomorrow afternoon and provide "lift" in the atmosphere. It will also bring in speed shear (winds increasing with height). This means that some isolated thunderstorms could develop rotating updrafts.

Tonight's batch of rain will exit the region early tomorrow morning. Widely scattered thunderstorms will then develop in the early afternoon and last into the evening. Some of these storms could quickly become severe with damaging winds and large hail. In addition, a brief tornado could also develop, however, I'm not expecting anything like what they saw in Mississippi today.

We will be tracking this through the day tomorrow and will bring you the very latest!

Strong Thunderstorms Possible Sunday

A strong upper storm system is headed east after producing tornadoes Thursday in Colorado, Kansas, and Texas. This storm may be responsible for more tornadoes Friday in the Mississippi Valley region. Virginia will begin to feel the impacts of this storm on Saturday with showers overspreading the area along with greater cloud-cover, but our risk for severe storms will arrive on Sunday.

We'll have a surge of low-level moisture from the southwest into Virginia on Sunday as the upper storm system nears. You can see the southwest surface winds into Central Virginia Sunday early afternoon, along with warm temperatures here:

And below is the resulting surge of rising dewpoint temperatures in the Commonwealth, which will approach 65 degrees Sunday afternoon:

At this time, the primary threat in Central Virginia appears to be for damaging winds, but we will be closely monitoring for the additional threat of tornadoes as well. Stay with CBS 6, we'll keep you ahead of the storm!

Dense Fog Thursday Morning

After Wednesday's soaking rainfall in Central Virginia, winds remained light overnight with decreasing cloud-cover higher up. These factors combined have allowed widespread dense fog to develop early Thursday morning, with most visibilities at a quarter-mile or less. There is a Dense Fog Advisory in effect for most of the area until 9 a.m., but it will take most of the morning for the fog to completely lift. Fog will be at its densest in low-lying spots and also along rivers, creeks, and streams. Skies will become partly cloudy this afternoon, allowing for a warmer afternoon in the mid-70's area wide.

Soaking Rain Showers

A good, soaking rain will continue to track northeast through Central Virginia today as an upper-level storm system passes overhead. Totals should run about a quarter of an inch or less, but this is still welcome rainfall as Richmond is now about 1.5" below average for the month. We'll have another round of rain this weekend as a large storm system approaches from the west. Here is the infrared satellite image Wednesday morning with the two storms depicted:

The second storm over the Western U.S. has a history of already producing severe weather out west, and this system is expected to bring strong to potentially severe thunderstorms to Central Virginia by Sunday.

Much-Needed Rain Chances

A couple of storm systems will bring some much-needed rainfall to Central Virginia, as our rainfall deficit has been growing over the past several weeks from our dry (and unseasonably hot at times!) stint of weather. Richmond is now about 1.5" below average for the month of April, just barely hanging on in the positive side for the year-to-date total (+0.52" from average). The first storm will arrive Wednesday and bring showers to the Commonwealth from around sunrise through Wednesday night. But a much larger, stronger, and slower-moving storm will arrive this weekend and linger in the region into early next week. We could also see strong thunderstorms in Central Virginia Sunday as the upper system gets closer to Virginia. We'll be tracking that system and let you know of any potential severe impacts.

More Seasonal Air Arrives for the Weekend

A cold front will move through the state overnight, bringing a more seasonal air mass into the region for the weekend. Highs in central Virginia were in the upper 80s to near 90 degrees Friday ahead of the front. Highs on Saturday and Sunday will stay in the 60s and very low 70s. Most locations will remain dry as the front moves through the area, with only isolated showers expected very early Saturday. The lack of rainfall in the past few weeks, combined with brisk northwest winds, will result in an elevated fire risk on Saturday. A northwest flow pattern will persist through much of next week, resulting in cool nights and slightly below normal highs.

Clear & Chilly This Morning

Temperatures have fallen early Thursday morning into the 30's in much of the Commonwealth as a result of clearing skies overnight, calm winds, and drier air settling into the Mid-Atlantic from a strong area of high pressure. Here are the 6:30 a.m. temperatures:

You can see the high pressure area parked right over Virginia this morning as well:

The low pressure system you see tracking through south-central Canada right now is going to bring a cold front into our state by early Saturday, with a chance for showers Friday evening into Saturday morning. Overall rain chances are very low, but it does look like we'll have some scattered light rain showers around Central Virginia Friday late afternoon and evening into Saturday morning while the front is tracking through. This front will also bring another shot of cooler air into the Mid-Atlantic, which will drop our high temperatures back into the 60's to around 70 degrees on Saturday, and holding in the 60's Sunday.

"Back Door" Cold Front

A "back door" cold front is making progress through the Commonwealth this Tuesday, generally tracking from the north-northeast to the south-southwest (hence, the name, "back door"). Temperatures are falling behind the front with the northeast wind shift into the upper-50's and low-60's. In addition, skies are becoming mostly cloudy with this system, and scattered light rain showers are tracking south. Here is the surface map at 12:42 p.m.

And here is the visible satellite image from about the same time:

You can see how temperatures have warmed with mostly sunny skies into the low-70's ahead of the front, whereas northern Virginia temperatures have been significantly impacted by the northeast wind, the cloud-cover, and the light rain. This front will be south of the Commonwealth by early this evening, keeping us mostly cloudy and cool overnight. Showers will continue to be possible from later this afternoon through the evening. Even though cloud-cover will gradually decrease through the day Wednesday, temperatures will still be cooler as a result of this cooler air mass moving into the Mid-Atlantic. Surface high pressure over the South will expand back into the Mid-Atlantic Thursday and Friday though, returning highs into the 70's.

A Brief Shift In The Weather Pattern

Temperatures for the past couple weeks have been way above normal across most of the Mid-Atlantic.

We aren't the only ones dealing with the heat. Check out temperature departures across the United States. You can see the most of the eastern half of the U.S. has been toasty while the western half has been cooler than average.

We are still watching for a brief transition in the weather pattern during the next couple weeks. NAO will dip below zero, which typically means near or below average temps.

You can spot the impact on next week's temperature forecast. Though it looks like this might not last long. We could be headed towards another warming period by the start of May!

Beautiful Start To Weekend!

After a strong cold front swept through Central Virginia last night (see severe weather reports here), rain is ending early this Friday morning and skies are also clearing from west to east.

Here's the visible satellite image at 7:30 a.m.:

High temperatures this afternoon will be about 20 degrees cooler than recent days, but that merely puts our temperatures back to average for this time of April. With clear skies overnight, lighter winds, and drier air, a cold start to both Saturday and Sunday mornings is expected, with lows dipping into the upper-30's and low-40's. No other significant chances for precipitation are in the forecast over the next week. A weak cool front will slide south into the Commonwealth Monday and Tuesday, bringing more cloud cover and reinforcing cooler air to the region.

Severe Threat Now Over

The strongest storms have now moved into the Chesapeake Bay and the atmosphere is now stable. Scattered showers will be possible for the next few hours, but the threat for severe thunderstorms is now gone. Enjoy sleeping tonight!

Tornado Watch Issued

Weather Update - 6:20 PM

Storms are beginning to fire out west and will eventually overspread central VA in the next few hours. For all you weather enthusiast out there, here is a link to a great website to help track storms as you hang out here on the blog...enjoy!

http://www.spc.noaa.gov/exper/mesoanalysis/new/viewsector.php?sector=17&parm=pmsl&underlay=1

Strong to Severe Storms Tonight

As Aaron mentioned yesterday, conditions are favorable for strong to potentially severe thunderstorms this evening and overnight in Central Virginia. A broad upper trough is approaching the East Coast today, with a strong surface cold front tracking east with showers and thunderstorms along and ahead of this front. Early Thursday morning, the cold front is tracking through central Kentucky, Tennessee, and Alabama. Once this front reaches western Virginia this evening, rain will start out west by 6 p.m. and reach areas east of I-95 by 11 p.m. A squall line will likely develop with frequent lightning, strong wind gusts, heavy rainfall, and potentially some hail. The risk for tornadoes is extremely low, but an isolated spinup could occur.

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!