Tornado Chaser's Winter Storm Herbert Forecast Thread

[Tornado_Chaser2005]

WINTER STORM HERBERT (A Pineapple Express System)
AREA FORECAST DISCUSSION
Wednesday, Jan 5, 2005 6:00 AM

DISCUSSION ... FOR ALL OF SOUTHWESTERN CALIFORNIA INCLUDING ALL OF ORANGE COUNTY ... SOUTHERN LOS ANGELES COUNTY ... WESTERN RIVERSIDE COUNTY ... AND SOUTHWESTERN SAN BERNARDINO COUNTY ...

SYNOPSIS....Winter Storm Herbert will slam into the forecast area late Thursday night, and peaking on Friday morning around sunrise.

...SHORT RANGE DISCUSSION...

PRE-STORM FACTS: SCATTERED SHOWERS WILL INCREASE AHEAD OF THE MAIN COLD FRONT, AND THE WINDS WILL BE GETTING STRONGER FROM THE SOUTHWEST.

THE RAIN CHANCES Winter Storm Herbert Looks excellent for rain producing. The rain should start to fall on Thursday Night, and increase throughout the night, ahead of Herbert's very strong cold front. Lets put it all in perspective for you. The dynamics with Herbert will be as follows. 850mb RH at 100%, and 850mb wind speeds from the South at nearly 50mph. This will set the stage for areas South and West of the San Gabriel, San Bernardino, and Santa Ana Mountains, at most risk for flooding, and a flood watch has been issued in result. All the above ingredients, get brought together at the right time, in the right place, on Friday Morning, on, or after sunrise. Should start to slow down in rainwise as the Front has passed.


THE THUNDERSTORM CHANCES Winter Storm Herbert Dynamics for Thunderstorms look excellent. The chances of Thunderstorms begins on Friday Morning after Midnight. The greatest chance of Thunderstorms will come along Herbert's cold frontal passage. The ingredients during this passage will be as follows: 850MB RH at 100%, 850MB wind speed from the South at 50mph, 500MB wind speed at 80mph, 250MB wind speed at 100mph, a -20C 500MB temp, with +10C temps at 850MB for an excellent tropical temperature gradient for a lot of Thunderstorms, and 700MBVV values reaching 45. These ingredients will set the stage for possible Bow Echo Thunderstorms along the cold front on Friday Morning, with damaging winds in excess of 70mph. The ingredients also set a stage for Thunderstorms possible about anywhere. This is a very dangerous situation, and please keep an eye on your local news station, or weather channel at time during the hours of Midnight, and 9am Friday Morning. Another thing to note, the helicity levels on the lower levels will be ranging near the 350 mark from after Midnight Friday Morning, till Frontal Passage. These levels, with cape values exceeding 750 will set the stage for possible rotation within the Thunderstorms. What this means is Tornadoes will be a possibility across the entire forecast area Friday Morning, and a Tornado Watch has been issued. A Severe Thunderstorm watch has been issued for the entire forecast area, due to the severe components coming together at the right time. Should start to slow down in Thunderstorm-wise as the Front has passed.



WIND CHANCES Winter Storm Herbert will have extreme winds along and ahead of the front. The Winds should start to increase from the Southwest Thursday Night, and peak inside the Cold Front on Friday Morning. Sustained winds to 30mph, with higher gusts will be the concern. Isolated 70mph gusts cannot be ruled out inside Bow Echo Thunderstorms as the front passes. And we all know around a Tornado, it is windy, so that will be a concern as well. The ingredients for this wind event will be 850MB Wind Speeds from the South of nearly 50mph, and a Very Powerful Cold Front. Winds should die down after the front has passed, but a High Wind Warning has been issued.

MEDIUM RANGE DISCUSSION...Winter Storm Herbert will be the weakest of the two systems coming in. Can you believe that? Another stronger system behind this one. To put in perspective, Winter Storm Grant was last week, and caused all the flooding, the Tornadoes sighted in Los Angeles, and the High Winds that knocked trees, and power out..I believe it was Tuesday morning of last week. It was Winter Storm Frank. Grant was the one we just had, but believe me when I say this. Winter Storm Herbert, the current one will be stronger than Winter Storm Frank was, and Grant. Winter Storm Isis, the one after Herbert Will be even stronger than Herbert, so we are in for it. Stay tuned for more forecasts on this very dangerous weather pattern.
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SPECIAL WEATHER STATEMENT
Wednesday, Jan 5, 2005 6:00 AM

Winter Storm Herbert will pound the forecast area beginning on Thursday Night, peaking sunrise Friday Morning, and Ending Midmorning Friday, With rain, flooding, Thunderstorms, which could turn severe, possible tornadoes, bow echo thunderstorms, and high winds.
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FLOOD WATCH
Wednesday, Jan 5, 2005 6:00 AM

A Flood Watch has been issued for the entire forecast area, from 9PM Thursday Night, till 9AM Friday Morning, a 12 HR Window. Expect Flooding to occur on already saturated grounds, and the burn areas.
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HIGH WIND WARNING
Wednesday, Jan 5, 2005 6:00 AM

A High Wind Warning has been issued for the entire forecast area from 12AM to 9AM Friday Morning, a 9 HR Window. Winds in excess of 70MPH along the front, with sustained winds before it at 30mph, with stronger gusts. Power will go out, so be on that alert..
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SEVERE THUNDERSTORM WATCH
Wednesday, Jan 5, 2005 6:00 AM

A Severe Thunderstorm Watch has been issued for the entire forecast area from 12AM to 9AM Friday, a 9 HR window. The Ingredients are showing in the analysis to be coming together for Severe Thunderstorms. A Severe Thunderstorm has winds in Excess of 58MPH, 3/4 inch diameter hail, or torrential downpours in excess of inches an hour. Bow Echoes can be a very big concern as the front passes Friday morning.
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TORNADO WATCH
Wednesday, Jan 5, 2005 6:00 AM

A Tornado Watch has been issued for the entire forecast area starting 2AM, and lasting till 9AM Friday morning, a 7 HR window. Helicity levels will start off nearing 200 value at the start of the window, and quickly jump to 300-350 value within a couple hours. Tornadoes will be possible across the entire forecast area, mainly areas along the coast, including Orange County, and Los Angeles Coasts. Areas inland could see Tornado Chances as well, so be on the alert as this Front nears, and passes. Areas of Tornado Concern will mostly be on the Palos Verdes area, northward to Santa Monica. A setup you saw last week with supercells coming off Catalina Island, and moving north into those areas will be a giant concern out ahead of the main cold front.
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Tornado Chaser

[aveosmth]

Good work TC!! These next 5-7 days will be ones to remember for SoCal.

[weatherlover427]

I can't believe the strong wording that the San Diego NWS used in their AFD this morning ... you almost never hear them talk like that. If they do, then you had better watch out.

[mikey mike]

when did winter storms start getting names?

[vbhoutex]

when did winter storms start getting names?

When TC started naming them.

[Tornado_Chaser2005]

vbhoutex, your right:), I feel its a bit easier to keep track of these system by naming them like hurricanes,lol.....Anyway, I take it this format is better, and to tell you the truth, I really like doing correct lower and upper cases. So much more easier to read,lol.

[vbhoutex]

vbhoutex, your right:), I feel its a bit easier to keep track of these system by naming them like hurricanes,lol.....Anyway, I take it this format is better, and to tell you the truth, I really like doing correct lower and upper cases. So much more easier to read,lol.

One thing to consider in your format is the use of the blue color in the text. At least for me it is tough to read against the blue background of he template I use. Maybe another color would work better? Of course it could be my advanced age eyes too.

[mikey mike]

ya got me TC!!

[Terry]

Very nice discussion and format, TC. It was easy to read and understand for winter weather wimpies like me.

I'm especially fond of your naming the storms. It make is much easier to follow and too remember.'

Now, if you can just manage to send me some winter weather (or even some good thunderstorms) in central FL, I'll really be happy.

[Tornado_Chaser2005]

FINAL FORECAST- WINTER STORM HERBERT (A Pineapple Express System)
AREA FORECAST DISCUSSION
Thursday, Jan 6, 2005 4:00 PM

DISCUSSION ... FOR ALL OF SOUTHWESTERN CALIFORNIA INCLUDING ALL OF ORANGE COUNTY ... SOUTHERN LOS ANGELES COUNTY ... WESTERN RIVERSIDE COUNTY ... AND SOUTHWESTERN SAN BERNARDINO COUNTY ...

SYNOPSIS....Winter Storm Herbert will nail the forecast area late tonight, peaking tomorrow morning, and ending in the afternoon. Rain, Thunderstorms, Tornadoes, High Winds, and Flooding will be the main concerns.

...SHORT RANGE DISCUSSION...

PRE-STORM FACTS: SCATTERED SHOWERS WILL INCREASE AHEAD OF THE MAIN COLD FRONT, AND THE WINDS WILL BE GETTING STRONGER FROM THE SOUTHWEST.

THE RAIN CHANCES Winter Storm Herbert Looks excellent for rain producing. The analysis is keeping Herbert on track as far as flooding goes. We could easily see above 4 inches at the coast, high in the valleys, and even higher in the foothills, and mountains. The rain will begin to fall tonight in the moisture ahead of the cold front. The rain will increase, so expect this. 850MB wind speed stands final to be at or around the 50 MPH mark, from the South. With 100% RH in the lower levels, expect that wind to carry this low level moisture above the forecast area until it hits the mountains. Now, I will teach you what happens when we have south winds, and 100% moisture at the lower levels. Ok, well the moisture will hit the Southern end of our mountains, and bounce up into the atmosphere, and make the clouds. These will rain down on us very hard and cause a lot of flooding. That is why the High Desert, to the North of the mountains, never see a lot of rain, because the moisture misses them, as it bounces back south from the mountains, drenching us to heck. Ok so, if you live South of the San Gabriel, San Bernardino, and Santa Ana Mountains, you are at the highest risk. Oh wait, that would mean the whole forecast area is. That's right, the whole forecast area will be at risk for flooding tonight. Mountains and foothills especially. The most dynamics will come around with the main cold front, and that will be after sunrise tomorrow morning. Around 10AM will be the peak in the middle forecast area.

THE THUNDERSTORM CHANCES Winter Storm Herbert Dynamics for Thunderstorms look excellent. The chances of Thunderstorms begin sometime after midnight tonight. They will last until the front passes tomorrow morning. We will have a saturated moisture at the lower levels, with sufficient 850MB winds at 50 MPH. this with a Jet Stream wind of nearly 115 MPH, and a mid level jet wind of nearly 80 MPH will cause a chance of some heavy duty Thunderstorms. Some of which could turn severe with damaging winds being the main concern. Not overly concern about large hail in these Thunderstorms as the temperature at the 650MB level will be too warm. 700MBVV values will be nearing 40, so that is not all that bad at all. In fact, that's very good for Thunderstorms creations. Note also the 500MB Temp will drop to nearly -21C Friday morning. This with a warm Low level will cause a temperature gradient. This gradient will be more than enough to spark off Thunderstorms. Keep in mind, this will not be like any other storm system. Our usual systems are cold, from the gulf of Alaska. This will be more like a Florida Thunderstorms event. Alot of warmth in this storm. Hence the name, pineapple express. A moisture feed from near Hawaii. Tropical in nature. Note that helicity levels could reach 400 value, so rotating Thunderstorms, with produce tornadoes will be a concern tonight across the entire forecast area. A Tornado Watch will stick, so will a Severe Thunderstorm Watch. Also keep in mind that the ingredients have green lighted to say a Bow Echo Thunderstorm will be very likely near the front. The Bow Echo could develop ahead, and within, 70 to 80mph winds, traveling in a straight line. This means that winds will travel from the bow echo storm, straight across the forecast area. Thunderstorm action will peak Friday Morning, and end Friday Afternoon.

WIND CHANCES Winter Storm Herbert will have very strong winds. Being the strongest system this season, Winter Storm Herbert's winds could reach Tropical Force Sustained winds, of winds as high as 40mph sustained, mainly along the coasts. If a bow echo forms in the Thunderstorms, a hurricane force wind will happen, in excess of 74 MPH. This is dangerous, and the ingredients have green lighted a High Wind Warning to stick across the forecast area. The winds should peak on Friday morning with the front, and calm down once the front has passed, being sometime late Friday Morning.

MEDIUM RANGE DISCUSSION...Winter Storm Herbert will be the weakest of the two systems coming in. Can you believe that? Another stronger system behind this one. To put in perspective, Winter Storm Grant was last week, and caused all the flooding, the Tornadoes sighted in Los Angeles, and the High Winds that knocked trees, and power out..I believe it was Tuesday morning of last week. It was Winter Storm Frank. Grant was the one we just had, but believe me when I say this. Winter Storm Herbert, the current one will be stronger than Winter Storm Frank was, and Grant. Winter Storm Isis, the one after Herbert Will be even stronger than Herbert, so we are in for it. Stay tuned for more forecasts on this very dangerous weather pattern.
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SPECIAL WEATHER STATEMENT

Thursday, Jan 6, 2005 4:00 PM

Winter Storm Herbert will pound the forecast area beginning on Thursday Night, peaking sunrise Friday Morning, and Ending Midmorning Friday, With rain, flooding, Thunderstorms, which could turn severe, possible tornadoes, bow echo thunderstorms, and high winds.
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FLOOD WATCH

Thursday, Jan 6, 2005 4:00 PM

A Flood Watch remains in effect for the entire forecast area, from 9PM Tonight, till 12PM Tomorrow Afternoon, a 15 HR Window. Expect Flooding to occur on already saturated grounds, and the burn areas.
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HIGH WIND WARNING

Thursday, Jan 6, 2005 4:00 PM

A High Wind Warning remains in effect for the entire forecast area from 12AM to 12PM Friday Afternoon, a 12 HR Window. Winds in excess of 70MPH along the front, with sustained winds before it at 40mph, with stronger gusts. Power will go out, so be on that alert..
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SEVERE THUNDERSTORM WATCH

Thursday, Jan 6, 2005 4:00 PM

A Severe Thunderstorm Watch remains in effect for the entire forecast area from 12AM to 12PM Friday, a 12 HR window. The Ingredients are showing in the analysis to be coming together for Severe Thunderstorms. A Severe Thunderstorm has winds in Excess of 58MPH, 3/4 inch diameter hail, or torrential downpours in excess of inches an hour. Bow Echoes can be a very big concern as the front passes Friday morning.
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TORNADO WATCH

Thursday, Jan 6, 2005 4:00 PM

A Tornado Watch remains in effect for the entire forecast area starting 2AM, and lasting till 12AM Friday morning, a 10 HR window. Helicity levels will start off nearing 200 value at the start of the window, and quickly jump to 350-400 value within a couple hours. Tornadoes will be possible across the entire forecast area, mainly areas along the coast, including Orange County, and Los Angeles Coasts. Areas inland could see Tornado Chances as well, so be on the alert as this Front nears, and passes. Areas of Tornado Concern will mostly be on the Palos Verdes area, northward to Santa Monica. A setup you saw last week with supercells coming off Catalina Island, and moving north into those areas will be a giant concern out ahead of the main cold front.
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PDS STATEMENT
Particularly Dangerous Situation

Thursday, Jan 6, 2005 4:00 PM

The first PDS statement ever given over this service. The helicity levels will be reaching nearly 400 tonight at 1km, so this is the setup for Tornadoes. The Low Level Jet will be more than enough for Low Level Rotation. This is to warn the forecast area, that this storm is not like other storms. It will be worse, and very bad. According to analysis, the threat for Tornadoes and Damaging winds is very likely, and this statement warning shall expire at 12PM Friday Afternoon.
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Tornado Chaser

[weatherlover427]

The local mets are really saying that this one could be huge ... lots of rain and flooding concerns with this next series of systems.