|
G-AIRMETs and GTG2 will become
operational in 2010! 
Very soon two aviation weather products are being
promoted to the
operational level. This includes Graphical AIRMETs
(G-AIRMETs) and the
Graphical Turbulence Guidance (GTG2) product. Both
products are currently in the experimental status and are ready to be
formally released as an operational product. These can
officially be used by pilots as a supplemental product when obtaining a
weather briefing prior to a flight.
At 1500 UTC on March
16, 2010, the G-AIRMET will no longer be considered
experimental and will become an operational product for pilots and
other stakeholders in aviation. G-AIRMETs were being prepared
by the Aviation Weather Center (AWC) in
concert with the traditional AIRMETs beginninng
on October 1, 2008. They were also released on the Aviation
Digital Data Service (ADDS) for public comment and feedback. Click here
to view the experimental product found on the Aviation Digital Data
Service (ADDS).
The aviation weather hazards depicted in the G-AIRMET include -
1. Surface visibility below 3 statute miles to include the
weather restricting the visibility.
2. Cloud ceilings with bases less than 1,000 feet AGL.
3.
Mountain obscuration where visual meteorological conditions cannot be
maintained including the weather causing the obscuration.
4. Moderate turbulence including the top and bottom altitudes
of the turbulence layer.
5. Sustained surface wind greater than 30 knots.
6. Non-convective low level wind shear potential at or below
2,000 feet AGL.
7.
Moderate icing including the top and bottom altitudes of the icing
layer. When the bottom altitude is given as the freezing
level,
the range of freezing level altitudes is also provided.
8. Freezing level contours at the surface and at 4,000,
8,000, 12,000 and 16,000 feet.
9. Multiple freezing levels including the height of the
highest and lowest freezing levels (example above right). Click here to view a complete
image.
The
G-AIRMET will be issued routinely at 0255 UTC, 0855 UTC, 1455 UTC and
2055 UTC and amended as necessary between routine issuances.
Each
routine issuance is valid through 12 hours with a standard time
resolution (interval) of three hours. These are referred to
as snapshots and are valid at a specific time, not smeared over a range
of two times. Click
here to view a FREE workshop that explains the advantages of
using G-AIRMETs.
Also, click here to read AIRMETs Get Graphic
from the November 2008
issue of IFR
magazine.
At 1300 UTC on February 9,
2010, the Aviation Weather Center will be implementing an enhanced
version of
the Graphical Turbulence Guidance (GTG) product referred to as GTG2 (as
shown on the left). Click here to view a complete
image. GTG has been an operational
product since
March 2003, but only provided guidance from 20,000 feet through 45,000
feet. Current is is found on the
ADDS website.
GTG and its newest version
is a product created automatically designed to provide guidance to
pilots and forecasters for the potential for upper-level,
clear-air turbulence (CAT). It does NOT provide guidance for
convective turbulence, turbulence
associated with thunderstorms or mountain wave turbulence. The enhancement extends
the current operational product down to 10,000
feet which is more in line with many general aviation aircraft. Keep in mind that this
field is
not a calibrated probability. In
other
words, it does not quantify the uncertainty with the length of the
forecast. Click
here to view the
experimental version of GTG2.
For
more information on GTG-2, click here to read Graphical
Turbulence, an article from the January 2009 issue of IFR magazine.
Don't
forget the Internet Wx Brief Roadmap
Are you a Regular member or Elite member of
AvWxWorkshops.com? Don't miss out! Simply login and
visit The Weather Report aviation
weather discussion forums. Here you'll find a categorical set
of forums along with Scott's Aviation Weather Blog and the Internet Wx Brief Roadmap.
All Regular and Elite members gain access to use the Internet
Wx Brief Roadmap. It's more than a bunch of bookmarks to your favorite
weather websites. The Roadmap is a rich set of NOAA/NWS
websites organized to help you with your preflight briefing whether
your departure is in three days or in three hours.
If
you are a frequent user of the Roadmap, please let other pilots know
about this unique product.
|
