surprise snow storm december 28 th 2012
DESCRIPTION
Surprise Snow Storm December 28 th 2012. Ben Miller Meteorologist National Weather Service – St. Louis, Missouri. Overview. My Midnight Shift Forecast Model Forecast Data from 00Z December 28 th 2012 HPC Snow Forecast My Snowfall Forecast What Happened? Radar Imagery - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/1.jpg)
Surprise Snow Storm December 28th 2012
Ben MillerMeteorologist National Weather Service – St. Louis, Missouri
![Page 2: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/2.jpg)
Overview My Midnight Shift Forecast
Model Forecast Data from 00Z December 28th 2012 HPC Snow Forecast My Snowfall Forecast
What Happened? Radar Imagery Total Snowfall Map
Where Did The Forecast Go Wrong? Satellite Imagery Synoptic Analysis An Ageostrophic Response Banded Snowfall Potential
![Page 3: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/3.jpg)
00Z FCST12/28/12
![Page 4: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/4.jpg)
12Z FCST12/28/12
![Page 5: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/5.jpg)
00Z FCST12/29/12
![Page 6: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/6.jpg)
x
x
x
xx
xx
xx
x
x
x
x
x
xx
x
x
x
x
xx
500 mb Vorticity Maximum fromthe 00Z forecast on 12/28/12
ECMWFGFSNAMSREF
GEMWRF
00Z12/28 12Z
12/28
00Z12/29
12Z12/29
![Page 7: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/7.jpg)
![Page 8: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/8.jpg)
HPC Mid Shift Snowfall FCST for 12/28/12
4-6”
![Page 9: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/9.jpg)
My Snowfall Forecast
![Page 10: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/10.jpg)
So What Happened?
Surprise!
![Page 11: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/11.jpg)
![Page 12: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/12.jpg)
Observed Snowfall from 12/28
![Page 13: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/13.jpg)
How Did That Happen?
![Page 14: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/14.jpg)
![Page 15: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/15.jpg)
![Page 16: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/16.jpg)
![Page 17: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/17.jpg)
00Z 28 December 2012
![Page 18: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/18.jpg)
12Z 28 December 2012
![Page 19: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/19.jpg)
00Z 29 December 2012
![Page 20: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/20.jpg)
X
![Page 21: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/21.jpg)
00Z 12/28/12 24 HR FCST of 295KMixing Ratio and Ageostrophic Wind
![Page 22: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/22.jpg)
00Z 12/29/12 00 HR FCST of 295KMixing Ratio and Ageostrophic Wind
![Page 23: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/23.jpg)
12Z NAM FCST on 12/28/12KFAMRed: OmegaYellow: Elevated CAPE
![Page 24: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/24.jpg)
Summary• Shortwave was a little stronger and took on a slightly
negative tilt
• Coupled jet developed
• Ageostrophic flow brought richer moisture farther north/northwest
• Limited instability allowed for banded precipitation
![Page 25: Surprise Snow Storm December 28 th 2012](https://reader036.vdocuments.net/reader036/viewer/2022062410/56816248550346895dd289ce/html5/thumbnails/25.jpg)
Questions and or Comments…
Except for Fred