Tuesday, February 21, 2017

So... is winter over??

You won't believe (or maybe you would) how many times I've been asked whether winter is actually over. The short answer? I think so.  Let's take a look...


First, if you think this was a "year without a winter," you are only partially right. It's been a while, and the recent heat has probably seered some brain cells, but December had some very cold periods. In fact, this blog spoke of at least three "Arctic blasts. Interspersed between some very warm days were multiple days with highs in the 30s and 40s. In fact there were low temperatures of 15° and 18° on consecutive days mid-month. Overall, December was about 1° above normal, mainly due to a few very warm days offsetting those cold ones.

Moving on, while January was very warm overall, we had 4 consecutive days with highs in the 20s and 30s and snow fell on Friday the 6th with most kids getting a snow day. There are many years when a snow day doesn't happen. Snowfall will end up below normal this year, but we only average about two small snow events a year. We got one. (And yes, I'm predicting we won't see another.)

Remember this snowfall on January 6? We didn't completely skip over winter this year!
After a top 10 warm January, February is likely on track to out-pace the warmth of January. As of the 20th, the average temperature for the month ranks third warmest on record...

Top 10 warmest February 1-20 periods on record, according to NOAA. 2017 ranks #3.

...and the forecast models indicate well above average temperatures to close out the month, with the exception of this weekend behind a Friday cold front.

The American-made GFS model ensemble system forecast temperature anomalies through the end of the month show plenty of warmth, with one "break" of near average temperatures this weekend behind a cold front that moves through Friday. (WeatherBell)
Looking towards March, we have a few products that can give us hints on what's to come. The first is NOAA's Climate Prediction Center outlook for days 8-14, which covers the first full week of March.

NOAA's day 8-14 temperature outlook, covering the first week of  March, expressed as percentage chance of above (below) normal. The Mid-South has a 60% chance of above normal temperatures. (NOAA/CPC)
No signs of any cold blasts there, with a 60% chance that temperatures will average above normal and a less than 10% chance they will be below normal. The week 3-4 outlook, which covers the period through the middle of the month shows a bit more promise, but even slightly below normal temperatures for that time of year would indicate highs near 60 (not winter, but not 80° either).

NOAA's week 3-4 temperature outlook, covering the period March 4-17, expressed as percentage chance of above (below) normal. The Mid-South has a 50% chance of below normal temperatures according to this graphic. (NOAA/CPC)

Finally, the NOAA temperature outlook for the entire month of March (issued last week), shows slightly enhanced odds of above normal temperatures for the month (first image below), while the March-May "spring" outlook indicates a decent chance of temperatures averaging above normal  (second image below).

NOAA's March temperature outlook, expressed as percentage chance of above (below) normal. The Mid-South has a 33-40% chance of above normal temperatures. (NOAA/CPC)

NOAA's March-April-May temperature outlook, expressed as percentage chance of above (below) normal. The Mid-South has a 40-50% chance of above normal temperatures (which according to their methodology means a 33% chance of near normal and a 17-27% chance of below normal temperatures). (NOAA/CPC)

Shifting from NOAA to the European model ensemble (basically the European model produced 50 times with slight variations and averaged), here is the latest temperature anomaly (departure from normal) map for the next 46 days (though April 6), also indicating above average temperatures east of the Rockies.

The European Ensemble model system predicts above average temperatures (overall) for the next 46 days. (WeatherBell)

And just for fun, the precipitation anomaly for the same period, showing the potential for a wet 6 weeks in the southeastern U.S.

The European Ensemble model system predicts a wet 6 weeks ahead for the southeastern U.S. (WeatherBell)

Does all this mean we won't see ANY more cold weather? Not necessarily. In fact, some areas will be back into the 30s again Sunday morning. However, it's POSSIBLE that the last freeze of the year has occurred in the city. The average date of the last freeze at the airport is March 19, which is still nearly a month away. I certainly can't rule out that still occurring. Our last 32° reading was February 16, While that is very early, if there isn't another freeze, it won't be the earliest last freeze on record, which was set 4 days earlier, on February 12, 1878!

The average last frost date is March 29, using 36° as a proxy for frost formation. There's still plenty of time for some 30s to affect the buds and blossoms that are arriving 2-3 weeks ahead of schedule, so if you have an itch to plant something, understand that frost, or maybe a freeze is still possible for some time yet.

The USA-National Phenology Network tracks the start of spring using models based on the Spring Leaf Index. Shown above is the spring anomaly through February 20, indicating that spring arrived in the Mid-South 2-3 weeks ahead of schedule.
So by all indications, spring has sprung and Punxsutawney Phil is #FakeNews! Just don't be surprised by a few chilly mornings mixed in with the occasional 80° day over the next month or so!

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Thursday, February 16, 2017

Warming weekend kicks off another warmer than average week ahead

Is it spring, winter, summer, or fall? While Mother Nature may still be undecided on the answer to that, the next week will feel more like early April than mid-February. That’s right, the warm weather is back and is shaping up to bring you a pretty good weekend in the metro.


Wide World of Warmth

The warming trend that started on Thursday will continue Friday as a ridge over the center of the country builds east. High pressure will remain over the region to end your work week, with temperatures jumping into the mid to upper 60s.

Temperatures are on the upswing over the next few days, as seen here in this temperature map (oranges/reds are 70s), with winds shifting out of the south to southwest. (PivotalWx)
Sunny skies will make Friday a pleasant way to lead into the weekend. A south to southwest wind will help usher in that warmer air too, leading to a more temperate overnight low in the 50s on Friday night. By comparison, our average high for this time in February is the mid 50s.


Showers on Saturday

The next chance of rain enters the picture Friday night into Saturday. A low pressure system moving across the Gulf of Mexico will throw the chance of showers north into the Mid-South overnight Friday night, though mostly scattered in nature. It will certainly not be a total washout on Saturday, with the best chance of showers coming between midnight and noon. Temps will still stay warm in the mid 60s.

Our next chance of rain will move through Friday night into Saturday. Though this NOAA surface map shows lots of green over the Mid-South, we’re expecting more scattered precipitation over the early part of the weekend
Showers and rain will be more likely the further you head south. If you’re traveling down through the Magnolia State, you could see a few thunderstorms too. These storms will likely not be severe across most of the state, though the Mississippi coast could see some stronger ones.

Overall, Saturday will be the only questionable day weather-wise over the holiday weekend ahead. Sunday will see clearing skies and warmer temperatures. 70+ degrees would not be a surprise over most of the metro area, with lows in the 50s.


70s in Command!

For those of you with extended weekends thanks to the Presidents Day holiday, Monday may be the best day of your weekend. Sunny skies and temperatures into the lower 70s will make you want to be outside soaking up some unseasonably warm rays. Lows in the 50s won’t feel bad either on Monday night.

The next system worth watching enters the picture for Memphis around mid-week. A low pressure center currently off the California coast will work its way across the west this weekend, and could bring rain and thunderstorms into the Mid-South by late Tuesday or Wednesday. Of course, MWN will keep you ahead of any incoming storms all through the next week. Looking further ahead, the temperature outlook indicates a very high likelihood of above average temperatures continuing into the last weekend of February.

The temperature outlook for Feb. 22-26 indicates a greater than 70% chance that above average temperatures continue across the Mid-South. (NOAA/CPC)

Want to get more updates from MWN? Check out our human-powered forecast and don’t forget to download the MWN app for your smartphone and tablet to get your daily dose of MWN in one complete package!

Alex Herbst, Meteorologist
MWN Social Media Intern

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Wednesday, February 8, 2017

Back to winter, for a minute...

Quickie blog today, mainly to pass on our "Social Media 6-Day" forecast to you. It's a continuation of the roller coaster ride we've been on lately! A cold front stalled over the area last night. As it pulled back to the north this morning right around sunrise, dense fog formed. it honestly was some of the "pea soup-iest" I had seen in a long time!


As I sat at the intersection of Winchester and Plough Boulevard on the northwest corner of the airport about 8:15am, I couldn't see the control tower. And not just the top of it, which happens sometimes, but NONE of it! And yet, there was FedEx, landing planes anyway! I marvel at how those jets and their flight crews can operate in such harrowing circumstances as not seeing the runway until you're over it.

The fog lifted by mid-morning and this afternoon, that front got one more push south, shifting wind back to the north, starting a temperature drop that will continue until tomorrow morning, when it will end up about 40° cooler than this afternoon's high just above 70° with wind chills down in the 20s. If you're heading out this evening, take a coat. Temperatures will be in the 40s with a gusty north wind up to 25-30 mph.


Tomorrow we're back to winter. Sun returns, but the mercury tops out in the mid 40s. A clear night is expected Thursday night with lows near freezing. As wind begins to shift towards the south Thursday night, it picks up Friday, pushing temperatures BACK into the 60s! South wind taps into some Gulf moisture Saturday with highs back above 70°, despite abundant cloud cover and widely scattered light showers or sprinkles dotting the radar.

The next cold front arrives Sunday with plenty of moisture and some instability to work with. Look for showers and thunderstorms, especially the second half of the day, and another warm one on tap as highs again reach near 70. Early next week looks like off and on showers with seasonal temps. More on that as it gets closer. Here's that forecast (and bless you...I know your sinuses love it):



Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Tuesday, February 7, 2017

January 2017 Climate Data for Memphis, TN

January Recap

After December broke a streak of six consecutive months ranked in the top 10 warmest for their respective months, January returned to the top 10 rankings, tied for eighth warmest January on record.  The warmth lasted nearly all month with just one spell of multiple days that were well below average temperature-wise, which also coincided with the first significant snowfall of 2016-2017 winter on the 6th. That early-month cold spell featured four consecutive days with high temperatures at or below 35 degrees and a couple of morning lows in the lower teens. However, three days later, highs were back above 70 degrees. After the 9th, only two days featured average temperatures below normal, and those were 1-2 degrees below an "average" day.

Warmest Januarys on record in Memphis, per the National Weather Service. 2017 tied for 8th warmest.
Precipitation was just a bit above normal at the airport, but below average at MWN in Bartlett with more than an inch and a half less than the airport recorded. Snowfall officially totaled 2.0" at the airport with reports across the metro varying from just under an inch to about three inches. No severe weather was reported and only one warning was issued, a Flash Flood Warning for far southern Shelby County and far northern DeSoto County on the 10th, which also happened to be the wettest day of the month as storms trained along the TN/MS border.


Memphis International Airport, Memphis, TN


Temperature
Average temperature: 48.5 degrees (7.3 degrees above average)
Average high temperature: 56.4 degrees (6.6 degrees above average)
Average low temperature: 40.6 degrees (8.0 degrees above average)
Warmest temperature: 76 degrees (12th)
Coolest temperature: 13 degrees (7th, 8th)
Heating Degrees Days: 503 (235 below average)
Cooling Degree Days: 2 (1 above average)
Records set or tied: None
Comments: The average temperature of 48.5 degrees ties for 8th warmest January on record. Seven days recorded sub-freezing low temperatures, which is 7.5 below the long-term average.

Precipitation
Monthly total: 4.26" (0.28" above average)
Days with measurable precipitation: 13 (3.5 days above normal)
Wettest 24-hour period: 1.50" (10th-11th)
Snowfall: 2.0 inches
Records set or tied: None
Comments: All snowfall occurred on a single day, January 6th.

Miscellaneous
Peak wind: South/47 mph (10th)
Average wind: 8.9 mph
Average relative humidity: 73%
Average sky cover: 70%

Click here for a daily statistical recap for Memphis International Airport.

Cirrus Weather Solutions / MemphisWeather.net, Bartlett, TN


Temperature
Average temperature: 47.9 degrees
Average high temperature: 56.0 degrees
Average low temperature: 39.1 degrees
Warmest temperature: 74.8 degrees (12th)
Coolest temperature: 10.8 degrees (8th)
Comments: None

Precipitation
Monthly total: 2.64" (automated rain gauge), 2.73" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 12
Wettest date: 0.82" (2nd) (via automated gauge)
Snowfall: 0.9 inches
Comments: None

Miscellaneous
Peak wind: Southwest/30 mph (12th)
Average relative humidity: 80%
Average barometric pressure: 30.07 in. Hg

Click here for a daily statistical recap for Bartlett, TN.

MWN Forecast Accuracy

MWN average temperature error: 2.79 degrees
MWN forecast temperatures within 2 degrees of actual: 53%
MWN average dewpoint error: 3.20 degrees
MWN forecast dewpoints within 2 degrees of actual: 53%

MWN's forecasts extend out five periods (2.5 days, or roughly 60 hours). Historical accuracy statistics can be found here.

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Visit MemphisWeather.net on the web or m.memphisweather.net on your mobile phone.
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder