Monday, March 31, 2008

Record rainfall at WXLIVE!

The old adage holds true... March came in like a lamb but is headed out like a lion! After rain and thunderstorms throughout the weekend that are only exacerbating flooding conditions, a flash flood watch is in effect through Tuesday morning as another powerful system heads our way tonight. Though some scattered thunderstorms could very likely break out this afternoon as we warm into the 70s, the heavy rain and possibly line of strong storms will not come through until the overnight hours. Many places will see another 1-2" of rain and with the ground already saturated from recent rains, it will all be runoff when it comes. Depending on just how quickly it comes, we could see flooding conditions, particularly around streams, rivers, and storm culverts that will be absorbing all of this water.

After a very dry couple of years, with drought conditions becoming extreme for part of 2007, we seem to be trying to make it up all at once. WXLIVE! (MemphisWeather.Net's official recording station in Bartlett) has recorded almost 7.5" of rain this month (with tonight's yet to be recorded). This has been the wettest month in WXLIVE!'s short history (since June 2005). We'll see if the trend continues in April. (It looks to be starting that way with another system bringing potentially heavy rain about 3 days out!)

Tuesday, March 18, 2008

Flash Flood Watch in effect

As mentioned a couple of days ago, the metro area is in for a good deal of rain over the next 24 hours. A Flash Flood Watch and Wind Advisory are in effect until 7am Wednesday. Today, temps will be mild with windy conditions. Everyone in the area woke up to temps in the upper 60s this morning and highs should top out in the mid 70s. Scattered showers will become more likely this afternoon. The heaviest rain will remain to our west over Arkansas where 3-6" is possible in some locations.

For tonight, models agree on moving the copious rainfall into the Mid-South as a slow-moving front hangs over the area and strengthening low pressure system tracks along the front. Many areas will see rainfall totals of 1-3" by tomorrow morning. In addition, as the front itself moves through after midnight, there is a good possibility of strong to severe thunderstorms. The timing looks to be between midnight and 4am for the heaviest thunderstorms. Lingering showers will hang around Wednesday morning with the sky clearing around sunset. An early look at Easter shows a good deal of clouds with a shower possible and coolish temperatures.

Sunday, March 16, 2008

Build an ark! It's headed our way...

After a pretty decent weekend, and an expected nice start to the work week on Monday, a slow-moving cold front will take its time moving through the Mid-South Tuesday and Tuesday night. An abundance of Gulf moisture will stream in ahead of the front, while there will also be enough dynamics to spark the development of thunderstorms Tuesday afternoon and evening, some possibly severe. This combination of ingredients will mean a great deal of rainfall for the area - possibly as much as 3-6" by Wednesday morning! Since the ground is already near saturation, the NWS has already issued a Flash Flood Watch, effective from 6am Tuesday to 6am Wednesday, for NE Arkansas, the Missouri Bootheel, counties in west TN that border the MS River (including Shelby), and DeSoto County, MS. Be sure to check out MemphisWeather.Net for the latest on the potential flooding episode.

Friday, March 14, 2008

More overnight thunder

After a fairly noisy night last night, with thunderstorms rumbling through the Mid-South, a repeat is likely tonight. Another low pressure system will move along a front that is draped across the region, bringing more t'storms after dark, lasting through the night. This system is a little stronger than last night, so there is a little better chance of severe weather with damaging wind and large hail the greatest threats. A few showers may linger into the morning hours, but will depart the area by lunchtime. The next round of weather will also be possible strong to severe t'storms late on Tuesday into early Wednesday. Temperatures this weekend will be seasonally mild with highs in the 60s. 70+ degree weather is expected Monday and Tuesday with windy conditions ahead of the next front as well.

Saturday, March 8, 2008

The morning after...

What a beautiful sight to wake up to! Everything is covered in a sea of white. My daughters had their warm weather gear and boots on before 7:00am this morning to "get the paper." Yeah right!

My final snowfall total was 3.8", though I suspect from surrounding readings that this is a little low, likely due to placement of the snowboard (which was the best I have but not ideal) and the wind that continuosly blew through the event and overnight.

Here are some readings from around the metro area, as reported by the NWS:

5 W Marianna, Lee County, AR 9.8 inches (HIGHEST TOTAL REPORTED)
NWS Memphis, Shelby County 7.2 inches
Atoka, Tipton County 6.5 inches
7 WNW Munford, Tipton County 6.5 inches
Ellendale, Shelby County 5.8 inches
4 E downtown, Shelby County 5.5 inches
3 E Southaven, DeSoto County 5.5 inches
2 SE Olive Branch, DeSoto County 5.5 inches
Memphis Airport, Shelby County 5.4 inches*** (OFFICIAL READING)
Germantown, Shelby County 4.9 inches
5 SW Olive Branch, DeSoto County 4.0 inches
3 N Bartlett, Shelby County 3.8 inches (MY TOTAL)
Earle, Crittenden County 3.5 inches
Hickory Withe, Fayette County 3.0 inches
4 W Brownsville, Haywood County 3.0 inches
Lakeland, Shelby County 3.0 inches
Byhalia, Marshall County 3.0 inches

And now a couple of pics we took this morning:

Finally, a satellite image from this morning that shows the snow cover over the area, heaviest in East Arkansas:

Friday, March 7, 2008

3.7" at 9:30pm

My last post of the evening - will write again tomorrow.

I measured 3.7" of snow at 9:30pm, with a liquid water equivalent (melted snow) of 0.19" - and I believe this amount to be low based on snow missing the gauge, blowing out, and some error in the measuring of the snowmelt. I expected about .30". It's still snowing lightly, with perhaps one moderate band left based on radar trends. I'll make a final measurement early tomorrow. It sure is pretty out!

7:00 update

I check the snowboard every hour on the half-hour - at 6:30 I had 2.5" and snow was still falling pretty good. Looks like a nice snow band has set up in east Shelby County, south of I-40. I'll bet it's really coming down hard there! NWS Memphis should end up with a very nice total when all is said and done. Last amount I have seen from the airport was 2". I'm posting some pictures below, taken about 5:30. My daughter and wife spent some time building a small snowman - not bad for just 2" of snow on the ground! It's good wet packing snow!

3:30pm - 1/2" down, more to go!

After about a half-hour of pretty good sleet, starting at 1:45pm, the snow starting coming, and coming... As of 3:30pm, my snowboard says we have 0.5". We're sitting pretty under what Meteorologists call the deformation zone on the backside of a low pressure system. Wrap-around precip on the backside of the low can sometimes be the best place to get good accumulating snows, and that is what we are getting. Radar shows a lot more precip across Arkansas still moving in this direction and between now and 9pm or so, we should be getting the heaviest part of the snow. I still think 3-4" is reasonable.

Temps fell a little more quickly than anticipated and WXLIVE! is now recording freezing temp of 31, where it should stay for several hours. Roads are wet, but bridges and overpasses are getting slick according to reports. As the sun sets, the rest of the roads will also get bad.

Below is a pic of me, ruler in hand, checking the snowboard out back - don't try this at home, I am a professional! :-)

12:10pm - Snow starts in Bartlett

The first flakes started coming down at WXLIVE! in Bartlett at 12:10pm. Expect the light stuff to continue for a couple of hours as temps fall to about 34. Forecast still looks good for heavier, accumulating, snow after 3pm with temps dropping below freezing after 8pm. Wind chills will be in the 20s throughout the event, so bundle up if you plan on venturing out!

By the way, looked through the official records for Memphis Int'l and found only three 3"+ snowfalls since 1999: Feb 2006 (3.0"), Feb 2002 (4.2"), and January 2000 (3.0"). Could we get the biggest snowfall in the past decade?? We'll see...


Everybody's waiting on the snow to fall! We didn't get the rain expected overnight last night - it went to our east. However, as of 10:20am, there is light rain moving north into the area from the south and snow falling across central Arkansas. With temps arond 37-39 right now, we will start off with light rain as temps fall. By shortly after noon, I expect rain to change to snow as the temperatures in the lowest few thousand feet of the atmosphere cool to the freezing point. A period of heavier snow will be possible later this afternoon and early evening. Scattered snow showers will continue overnight with a total of 3-5" still expected. Temps will remain above freezing until after sunset with a low tonight in the 20s. Gusty wind will make it feel even colder today as temps falls through the 30s. Roadways will likely become slippery by this evening and all secondary roads could be treacherous by morning.

I'm looking forward to this as much as you are! Feel free to post your comments and/or your snowfall totals here.

Thursday, March 6, 2008

Snow forecast update

Will be issuing my MemphisWeather.Net forecast shortly and will concentrate on tweeks to the short term, including expected snowfall totals. Bottom line, the potential for a good amount of snowfall (for Memphis) or a great forecast bust are high! I tend to lean towards the first.

Would not be surprised to see northern parts of Shelby County and Tipton County get 3-4" while the rest of Shelby Co. gets 2-3". DeSoto and Fayette Counties may also see 2-3" while Crittenden County and West Memphis get 2-4" (less to the south and more north).

Timing: rain should begin mixing with snow after 10am, then change to all snow after 1pm. It will continue the rest of the afternoon, perhaps at it's heaviest between ~4-8pm, then taper after midnight. The NWS is also indicating 3-5" for Memphis and Shelby Co.

As for expected road conditions in the Memphis area: Roads should be fine through mid afternoon with the first inch or snow of snow melting on contact. By evening, as sun sets and snow continues to fall, slushy conditions will be likely. Overnight, as temps drop below freezing about 10pm, roads could accumulate a little snow, but not as much as grassy surfaces. Slush could freeze over by morning, making early Saturday morning treacherous.

Below you see one of the maps that we forecasters might look at. It's a 48-hour total snowfall map for the Mid-South based on a model called the NAM. Not necessarily the "truth," but a piece of info we use to try and forecast that "truth."

Let it snow!

The brief dose of winter on Tuesday morning, in the form of light snow, may have just been a prelude of things to come as the first week of March is providing some of our best chances at winter weather! A cold front is moving through the area today, putting us on the back (cold) side of it, as low pressure develops over the western Gulf and moves east-northeast through the Gulf Coast states tonight and tomorrow. The low will draw moisture up into the area that will start as rain overnight tonight with temps around 40. By tomorrow, the rain will mix with then change to snow from northwest to southeast as colder air moves in behind the departing low. This transition should take place sometime shortly after noon if computer models are correct, with the possibility of a little sleet mixing in with the rain during the late morning hours. accumulating ice is not expected.

Enough precipitation will linger into the afternoon and overnight Friday that the metro area could pick up as much as 2" of the white stuff! Areas well to our north and west will see sleet and snow overnight and snow all day tomorrow, so northeast Arkansas could see as much as 5-8" of snow! I think 2" is pretty good for the Memphis heat island though. Lows will drop below freezing Friday night and Saturday's highs will be in the mid to upper 30s, so the snow should stick around at least through the morning on Saturday before the sun melts it away.

Of course, since this storm is being "played up" in advance, it will probably bypass us and we'll just see some flurries... stay tuned!

Be sure to visit MemphisWeather.Net for the latest on this developing winter weather scenario.

Saturday, March 1, 2008

An interesting 72 hours coming up

What a great weather weekend we are starting March off with! March has come in like a lamb in Memphis. It's 70 degrees as I type this and it should be a few degrees warmer tomorrow as south wind, clouds, and humidity increase as well. Should remain dry until Monday morning though. Monday and Monday night will be windy with plenty of rain on tap. Most t'storms should stay south and east of the city as low pressure moves just to our SE Monday night. The heaviest rain will likely be Monday evening with a couple of inches possible by Tuesday morning.

Then it gets interesting... cold air pours in as the low departs and lingering rain could change to snow by Tuesday morning's rush-hour, with scattered light snow showers continuing Tuesday as temps remain in the 30s. Brrr!! Definitely a change from Sunday and Monday! Computer models still disagree on the amount of precip lingering Tuesday as the cold air moves in, and exactly how cold it gets in the metro area, but given that it is March, I would be surprised if the we got more than an inch. Stay tuned!