Friday, August 26, 2016

Elevated Ozone Near Antelope Island Fire Observed by KSL Helicopter

Antelope Island Fire seen by NASA Aqua Satellite on 23 July 2016
The KSL-5 News Helicopter is equipped with an Ozone and PM 2.5 sensor on July 23, 2016 the helicopter flew to a fire on Antelope Island in the Great Salt Lake. When the copter flew in the smoke the PM 2.5 and ozone concentrations increased.

Wednesday, August 24, 2016

Lawn Watering Maintenance: Idea for Property Maintenance Managers

Here's an idea. Maybe I should commercialize the idea and make some money...Use Google Maps to identify broken sprinkler heads and insufficient watering of large lawns, school, city parks, golf courses, etc.

These images where pulled off Google maps and you can see distinct patterns in the greenness of the lawns that depend on the effective use of the sprinkler systems. The property or city maintenance manager could look at these images, identify sprinkler heads that do not work properly by the area of dead grass. Of course, this idea only works as frequently as Google updates their maps. Definitely an interesting idea here.

RAPv3 and HRRRv2 Release Notes

Tuesday, August 23, 2016

Upgrade to the RAP and HRRR model

The above link explains that the RAP and HRRR weather models used operationally by the National Weather Service were upgraded to RAPv3 and HRRRv2.

Effective on or about Tuesday, August 23, 2016, beginning with
the 1200 Coordinated Universal Time (UTC) run, the National
Centers for Environmental Prediction (NCEP) will implement
Version 3 of the Rapid Refresh (RAP) and Version 2 of the High-
Resolution Rapid Refresh (HRRR) systems.

Major Changes:

A major change to the RAP will be an expanded computational
domain which will now include Hawaii. This expansion will
facilitate future NCEP plans for ensemble systems and, in time,
improve the initialization of Short Range Ensemble Forecast
(SREF) members that use the RAP for initial conditions.

Analysis Changes:

Both the RAP and HRRR will use an updated version of the
Gridpoint Statistical Interpolation (GSI) analysis code.
Refinements are made to the GSI to improve the assimilation of
surface observations, soil moisture adjustment, and three-
dimensional cloud and precipitation hydrometeors. In addition,
the HRRR will start using the ensemble/hybrid data assimilation;
it is already used in the RAP, but the weighting of the ensemble-
based component in the RAP will increase from 0.50 to 0.75. In
addition, while the RAP already cycles land-surface states, this
cycling is being introduced into the HRRR. In HRRR Version 1, all
runs are independent.

Other analysis changes include:

-Assimilating radial wind and mesonet data
-Applying PBL-based pseudo-innovations for 2-meter temperatures
(already used for 2-meter dew points)
-Changing the cloud-hydrometeor assimilation to avoid METAR-based
cloud building when satellite data shows clear skies at all times
of day (currently used just in daytime)
-Introducing direct use of 2-meter temperature and dew point
model diagnostics in the GSI.

Specific to the HRRR, the application of radar reflectivity data
in the GSI to direct specification of 3-dimensional hydrometeors
is increased to apply to a broader range of weather conditions,
including warm-season events with reflectivity up to 28 dBZ.

Changes to Model:

- The RAP and HRRR will both begin using WRF version 3.6.1; both
will continue to use the ARW core.
- The MYNN planetary boundary layer scheme is being updated to
include the effects of subgrid-scale clouds. The mixing length
formulation in the boundary layer scheme and thermal roughness in
the surface layer are being changed.
- The 9-level RUC land-surface model is being updated to add a
mosaic approach for fractional snow cover, improve the fluxes
from snow cover, and modify the wilting point for cropland use.
- Major updates are being made to the Thompson microphysics
scheme, including making it aerosol-aware with use of an ice-
friendly and water-friendly aerosol field.
- Shortwave and longwave radiation have been changed to use the
RRTMG (RRTM global) scheme that includes the effects of aerosols
and boundary layer subgrid-scale clouds.
- The WRF-ARW diagnostics for 2-meter temperature and dew point
are being improved. 
- The convective scheme in the RAP is changed from the Grell 3-D
scheme to the scale-aware Grell-Freitas scheme. The HRRR, at 3 km
horizontal resolution, explicitly resolves convection and does
not use a convective scheme.

Many of these changes to the data assimilation, land-surface
model, boundary layer scheme, microphysics, radiation, and (in
the RAP only) convective scheme are designed to mitigate the low-
level warm, dry bias in the RAP and HRRR, most notable during
afternoons in the warm season. Significant reduction of these
biases has been evident in extensive testing.

Output Changes:

- The HRRR directory structure will be migrated out of
"nonoperational" on the NCEP ftp and http servers. Data will also
be available on both the primary and secondary servers.

Wednesday, August 10, 2016

Rain and Hail in Spanish Fork

It's raining and hailing in Spanish Fork...
Time: 18:50 UTC

You can see the cooler air accompanied by the storm from the temperature and dew point time series...Temperature goes down, and wet bulb (humidity) goes up. When the temperature and dew point temperature are the same that is about all the cooling that can be done by evaporation...a natural air conditioner.

There is some good cloud development shown up in the satellite images...
Time: 18:56 UTC

One interesting aspect of this storm is how the HRRR model handles it. The latest analysis hour has the reflective in the right spot, but the HRRR model gets rid of the storm by the first forecast hour. The storm has lasted into that hour, and so this is a case that the HRRR model is not useful for a short term forecast of this storm.
Time: 17:00 UTC
 Now look at the one hour forecast...the hail storm has disappeared. Yep, not really a useful short-term forecast.
Time: One hour forecast valid at 18:00 UTC

Friday, August 5, 2016

Box Elder County Fire

On August 4th a fire in Box Elder County made quite a bit of smoke. Here's a view from the Aqua satellite:

The smoke spread to much of the Wasatch Front. This picture is looking down State Street in Salt Lake... (no mountains!)

And driving into Cache Valley.

Wednesday, August 3, 2016

HRRR under-predicting temperature the last few days

HRRR Temperature Verification at KSLC and UKBKB between July 31st, and August 3rd, 2016.

The HRRR model is running an average of 3.4 degrees too cold over the last few days. Top shows the temperature observed at the SLC airport (red) and the HRRR analysis. Next is the HRRR temperature bias (HRRR-Observed)

On the other hand, the HRRR analysis for Spanish Fork (UKBKB) is much better, and is on average 1.1 degrees too warm...

Monday, August 1, 2016

July 2016 was a Hot One

Did you think July was hot?? It sure was! The second half of the month we observed higher than normal temperatures every day.