MESO, Inc. MM5 Real Time Forecast for 08-Mar-1999 Colorado Front Range Snowstorm Bust
This case was a local Front Range snowstorm bust. The forecast from the evening before (Sunday 7 Mar)
was for overnight/early morning Front Range snowfall. A forecast (or event) like that has a significant
effect on Front Range commuters. This forecast was run after-the-fact, but could have been
produced in real time, before the Sunday evening news broadcasts. This forecast also over-proedicted the Front Range precipitation, but the mesoscale precipitation, wind, and temperature patterns would have helped
the forecaster. Below is a quick look at the model forecast of
24 hr accumulated precipitation, valid at 5 am Monday morning, as well as the surface temperatures and winds at that time. Browse the point/click tables for more detailed information.
Coarse (30 km resolution) and nested grid domains (10 km resolution):
Grid configuration: The coarse domain has 93 x 78 points horizontally with a 30 km
grid spacing. The nested domain has 76 x 61 points horizontally, with a 10 km grid spacing.
Both domains have 25 layers in the vertical, with the model top at 75 mb. Both domains
are run for 36 hours. The nested domain land surface characteristics (terrain, land/water,
sea surface temperature, land use, soil moisture, snow cover) are all interpolated directly
to the nested grid scale; as a result the nested grid has features consistent with that scale and
is not just an interpolation from the coarse grid information.
Grid 1 configuration
Grid 1 topography
Grid 1 topography (alternate graphic)
Grid 1 land use
Grid 1 land/water distribution
Grid 1 sea surface temperatures
Grid 2 configuration
Grid 2 topography
Grid 2 topography (alternate graphic
Grid 2 land use
Grid 2 land/water distribution
Grid 2 sea surface temperatures
Model configuration: NCAR's MM5v2 version 2.9
Simple ice microphysics (coarse and fine grids)
Kain-Fritsch cumulus parameterization (coarse and fine grids)
MRF PBL (coarse and fine grids)
Cloud-scheme radiation (coarse and fine grids)
Radiative top boundary condition (coarse and fine grids)
2-way interactive nesting
Initialization: This run is initialized at 1200 UTC 7 March 1999. The 0 hour forecast from
the current 0000 UTC Early Eta run (Eta 211 grid, grid has 80 km data resolution, actual
model run has 32 km resolution) is used as the first-guess. The 1200 UTC rawinsonde and
surface METAR observations are used to enhance the first-guess using NCAR's MM5
RAWINS package with the multi-quadratic analysis scheme.
The Eta forecast fields at 06, 12, 18, 24, 30, and 36 hrs are used for the lateral boundary
conditions. The fine grid surface
characteristic fields (terrain, land/water, vegetation, SST) are interpolated
to the fine grid directly from the original data. The fine grid initial
fields are interpolated directly to the fine grid (not from the coarse grid).
Soil moisture and snow cover: The soil moisture availability is updated during the model run, using
the modifications provided by Jim Bresch at NCAR/MMM. The soil moisture
availability (SMA) is initialized for each run using the Eta 12 hr fcst SMA from the previous
Eta run (the previous 12Z run). The snow cover (just yes/no, not snow
depth) is updated during the model run using the IFSNOW option in the model.
The snow cover is initialized from the most recently available NESDIS IMS snow
cover analysis.
Current MESO MM5 runs are initialized at: 07-MAR-1999 1200 UTC
NCEP model used for first-guess is ETA from 99030712
Tabular site forecasts (Now with point-and-click map, many more locations)
Vertical Cross-Sections
MESO MM5 RT Grid 1 Soundings, Initial time= 07-MAR-1999 1200 UTC
(Sunday, MARCH 7, 5 a.m. MST)
Forecast hr
Valid Time (MST)
Valid Date | 00 hour
5 am
7-MAR | 06 hour
11 am
7-MAR | 12 hour
5 pm
7-MAR | 18 hour
11 pm
7-MAR | 24 hour
5 am
8-MAR | 30 hour
11 am
8-MAR |
| Salt Lk Cty Sdg | 1200 |
1800 |
0000 |
0600 |
1200 |
1800 |
| OKC Sdg | 1200 |
1800 |
0000 |
0600 |
1200 |
1800 |
| Dodge City Sdg | 1200 |
1800 |
0000 |
0600 |
1200 |
1800 |
|
Grid 1 animations: Click on link to load, and then click on your browser's
"reload" to loop.
Animation of Grid 1 MSLP
Animation of Grid 1 Vis Sat View
Animation of Grid 1 6-hrly Precip
Animation of Grid 1 Total Precip
3-D Cloud Animation!
Grid 1 Vertical Cross-Sections
Grid 1 Tabular Site Forecasts
Grid 2 animations: Click on link to load, and then click on your browser's
"reload" to loop.
Animation of Grid 2 MSLP
Animation of Grid 2 Vis Sat View
Animation of Grid 2 3-hrly Precip
Animation of Grid 2 Total Precip
3-D Cloud Animation!
Grid 2 Vertical Cross-Sections
Grid 2 Tabular Site Forecasts
For more information on MESO's MM5 modeling capabilities contact info@meso.com
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