Severe Weather Outlook For May 25th 2012
We are going to start this off with looking at the current surface map..
http://www.hpc.ncep.noaa.gov/sfc/90fwbg.gif
You can see there is a cold front that goes from western Upper Michigan and then South and southwest wards. Behind this cold front is yet another cold front .. This cold front should become stationary..
http://www.hpc.ncep.noaa.gov/basicwx/92fwbgus.gif
Then begin to lift north as a warm front..
http://www.hpc.ncep.noaa.gov/basicwx/93fwbgus.gif
Now to be quite honest we are not that enthused with any severe weather happening to much during the day time because what is happening is that as the warm front lifts north this is bringing ridging over top of the region where the air mass has become moist and unstable. However..we have a lower level jet that will be strengthening as the evening goes on and we anticipate that coverage should increase. We have never been a proponent of severe weather from a warm front..so over all we are not expecting an extremely active day and as well there really is no impulse or piece of energy to add any fuel to this. This will all essentially be driven by low level warm air advection..
So lets look at the parameters that are in place on tonight's guidance..
TEMPERATURES
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_TMPF_2_M_ABOVE_GROUND.png
They will be from 70 to as high as near 100 depending on where you are located..
DEWPOINTS
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_DPTF_2_M_ABOVE_GROUND.png
50s and 60s with some smaller isolated 70 degree dew point readings.
CAPE
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_CAPE_SURFACE.png
Depending on where you are we range from 500-4000
LIFT INDEX
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_PLI_30_0_MB_ABOVE_GROUND.png
Lift index is from 0 to about negative 13 depending where you are located.
ENERGY HELICITY INDEX
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_EHI_1000_M.png
NOW..IF there is to be any tornado's today it would be in the following locations:
Southern part of Iowa into Southern Part Of Nebraska
Northern Missouri
All of Kansas
Oklahoma (all but the area not in the severe zone)
These areas would be at greatest risk for a tornado to occur because of the EHI being at 1 or above which could create super cells. One problem that will be fighting this however is the CAPPING that is coming in over top..
Greatest HELICITY is in NEBRASKA
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_HLCY_1000_M_ABOVE_GROUND_0_M_ABOVE_GROUND.png
This is also where the most moisture "should be" so this increases the potential for tornadic activity to occur ..which we feel should be at about 5% in that area..Again, not a terribly high risk but the risk is there..
And last but not the least is the SHEAR in place..
http://www.twisterdata.com/data/models/nam/221/maps/2012/05/25/00/NAM_221_2012052500_F24_SHRM_500_MB.png
30-60 knots should be in place across the region..
GFS also suggests that lapse rates should be 6.0 or above which suggests that large hail is also going to be a possibility.
Overall the main threats will be winds and Large hail but the areas highlighted above should not be surprised to see the possibility of a tornado especially as the lower level jet increases. It is all going to be dependent on how much moisture return we can get with the ridging building in!
No comments:
Post a Comment