Clouds and Precipitation at 1 km between Data Points
Description
This animation is a visualization of the Deep Thunder forecast
for the highest-resolution nest at 1 km resolution focused on New York
City. Each time step corresponds to 10 minutes of forecast time.
They show the local terrain as a shaded surface that is colored by contour
bands of total precipitation (as rain in inches), following the scale to
the upper right, where brown implies no rain (dry) and heavier rainfall
is in darker shades of blue. If the model predicts no precipitation
then a similar visualization of humidity will be shown instead. If
areas where precipitation is forecasted are sufficiently cold, then they
may be marked with large or small Xs for snow. The smaller markers
imply light snow or flurries. In animation, areas of precipitation
will appear to "paint" the surface blue. However, the model calculations
require some time to "spin-up" the microphysics to enable precipitation.
Therefore, there will typically be no precipitation in the first couple
of hours of model results.
Since the precipitation is accumulated through the model run, regions which stop
showing changes in color imply that the precipitation has ended. In some cases
when that happens and the temperature is sufficiently cold, snow markers may appear.
This implies that wet surfaces may be beginning to freeze.
The terrain is overlaid with maps of coastlines and county boundaries
in dark gray and major roads in light gray. Individual landmarks
and cities are shown by name. The terrain map is in a three-dimensional
scene with predicted clouds. The clouds are shown as a translucent
white (boundary) surface derived from a threshold of total cloud water
density (liquid and ice) where the ratio of that total to the contents
of the atmosphere is 0.0001 kg of water per kg of air. If the model
predicts severe weather, such as convective activity that could lead to
the formation of thunderstorms, then a translucent cyan surface may be
visible within the clouds. The region within this cyan surface corresponds
to where precipitation is forming within the clouds (e.g., rain shafts)
and where any storm activity would be the most severe.
Instructions
An animation (compressed as an MPEG-1 video) is shown above with 10
minutes of forecast time between each frame. Depending on your connection
speed and that of your computer, the animation may take a few minutes to
load and decompress in your browser. The progress of that process
is shown until it is completed. When it is completed, the animation
will play. There are VCR-like controls under the animation to enable
you to stop playback, play forward or backward, or step through the frames
one at a time. If you are having problems viewing or interacting
with this animation, make sure your browser has Java and Javascript enabled.
If you are still having difficulty, you can download
the mpeg file directly.
More Visualizations of
the Current Forecast
Learn More about These Forecasts
Recent High-Resolution Local Satellite
Observations
Learn
More about Deep Thunder
Learn
More about how Deep Thunder Visualizes the Data Generated by the
Weather Model
Current Weather
Information and Predictions for New York City (from the National Weather
Service)
Current Model Results from the National
Weather Service
Recent High-Resolution Local Radar Observations
Evaluation of Recent Forecasts
