Current Deep Thunder Forecast for New York
Atmospheric Stability at 1 km between Data Points (K Index, Lifted Index and Vertical Winds)
Description
This animation is a visualization of the Deep Thunder forecast
for the lowest-resolution nest at 16 km resolution focused on New York
City. Each time step corresponds to one hour of forecast time.
The specific data shown are for potential use for aviation applications.
In particular, the data may be useful in indicating the potential for severe
weather due to convection. A colored surface is shown, where the
color corresponds to K Index, which is a measure of conective potential
based on the vertical lapse rate along with the amount and vertical extent
of low-level moisture in the atmosphere. The surface is deformed
linearly by Lifted Index, which relates to the potential instability from
the surface to 500 mb. Significant deformation from a plane would
imply regions of potential instability. The following table summarizes
a relation between lifted and K Index. But there is variation with
season and location.
Lifted Index
(Instability increases with greater negative values) |
K Index
(Instability increases with greater positive values) |
Probable Weather |
Operational Impact |
| Negative (unstable) -- Low |
High (wet) -- Pink |
Showers or thunderstorms |
Turbulence, may be hazardous |
| Negative (unstable) -- Low |
Low (dry) -- Cyan |
Some cumulus activity; light precipitation |
Bumpy with thermals |
| Positive (stable) -- High |
High (wet) -- Pink |
Stratus clouds; steady precipitation |
Poor visibility; light winds |
| Positive (stable) -- High |
Low (dry) -- Cyan |
Predominately fair |
Smooth air; light winds |
The surface is overlaid with a set of contour lines of forecasted vertical
wind speed. Significant updrafts (green to yellow contours) in blue
"valleys" on the surface would imply regions of significant potential forsevere
convective activity.
The surface is also overlaid with maps of coastlines in black, state
and national boundaries in white and rivers in blue.
Instructions
An animation as a set of individual JPEG images is shown above with
one hour 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. 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, control the speed of playback, etc. If you are having
problems viewing or interacting with this animation, make sure your browser
has Javascript enabled.
If the forecast information presented on this page does not seem to
be current and you have visited this site recently, the results of the
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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
