NOAA Weather Forecast Today says 0 degrees

[Scot]

The National Weather Service must be getting a sense of humor.  My forecast (37122) for this afternoon says COLD with a high of 0

[jilly]

haha mine too -

[Thundersnow]

I love the "unseasonably cool" part.  rofl

[Kevin]

When this happens it means the WFO has slipped in a "blank" temperature grid into GFE (the forecast making software in AWIPS). It could have been at just one hourly point out of the entire day...but if it slips all the way through it gets reflected in the forecasts. You can even tell that by the language saying "temperature rising into the upper 60s after midnight"...which shows the rest of the grid points are normal (actual low in the upper 60s). I'm sure they'll get it corrected very shortly...

[ajatwister]

Boy I wish this was true. I'm sick of this darn heat 

[toastido]

Along the same lines is this screenshot from my sister's phone yesterday afternoon:

[Kevin]

The reason why that happened...KNBA reported "GS" at one point...which is the coded observation for "small hail". However...it is also the code for "snow pellets"...

Here it is...
KBNA 152019Z COR 18017KT 1/2SM R02L/3000VP6000FT +TSGSRA FG SCT014CB BKN060 OVC130 21/19 A2980 RMK AO2 TSB06RAB11GSB14 FRQ LTGCG S-OHD TS S-OHD MOV E P0022 $

[toastido]

The reason why that happened...KNBA reported "GS" at one point...which is the coded observation for "small hail". However...it is also the code for "snow pellets"...

Here it is...
KBNA 152019Z COR 18017KT 1/2SM R02L/3000VP6000FT +TSGSRA FG SCT014CB BKN060 OVC130 21/19 A2980 RMK AO2 TSB06RAB11GSB14 FRQ LTGCG S-OHD TS S-OHD MOV E P0022 $

GS == Graupel if I'm not mistaken.  Graupel is actually 'soft hail', which is indeed interchangeable with 'snow pellets'.   I'm betting the reason it said wintry mix though, was the RA (rain) immediately afterwards.  I'm thinking the decoder used on that METAR ob should have looked at the T/D reading (21/19 == 69.8F/66.2F) before deciding it meant snow pellets instead of soft hail. 

[Kevin]

GS == Graupel if I'm not mistaken.  Graupel is actually 'soft hail', which is indeed interchangeable with 'snow pellets'.   I'm betting the reason it said wintry mix though, was the RA (rain) immediately afterwards.  I'm thinking the decoder used on that METAR ob should have looked at the T/D reading (21/19 == 69.8F/66.2F) before deciding it meant snow pellets instead of soft hail. 

Yep...the rain with it likely created the "wintry mix" that appeared on-screen. Most METAR decoders don't account for the hail possibility though. GS is usually only used if the hail is 1/2" or less...you're supposed to use GR if its larger (at least when you have on-site observer...which BNA does).