Author Topic: STS-120: Launch Weather Forecast (Read 19670 times)

psloss · « **on:** 10/20/2007 12:46 pm »

Starting the launch forecast thread for Rob...

The L-3 forecast from the 45th Weather Squadron is out...no big changes from yesterday's forecast that carries a 40% probability of KSC weather prohibiting launch. Direct link to the PDF file:
http://www.patrick.af.mil/shared/media/document/AFD-070517-025.pdf

Excerpt:

Quote

On launch day, high pressure will be located off of the east coast of the US causing southeasterly flow over Central Florida. With this weather pattern, there is a threat of coastal showers, cumulus cloud development, and a low cloud ceiling at the onset of the east coast sea breeze near launch time. Our primary concerns for launch day are cumulus clouds, showers, and a low-cloud ceiling. The weather is similar the following day as well, and a front may be approaching the area by the 48-hour delay time.

(Their emphasis.)

The L-4 numbers from the Spaceflight Meteorology Group (SMG) are also available online, with the "chance of showers within 20 nautical miles noted in the forecast sheets:
http://www.srh.noaa.gov/smg/smgwx.htm

psloss · « **Reply #1 on:** 10/21/2007 11:50 am »

The latest launch weather forecast is out (link above); no major changes.

Here is the latest weather forecast from Spaceflight Meteorology Group for the primary abort sites on Tuesday:
http://www.srh.noaa.gov/smg/SMG_prod.php?pil=OAV&sid=JSC&version=0

Quote

NOUS54 KWNJ 211044
OAVJSC

NOAA/NATIONAL WEATHER SERVICE
SPACEFLIGHT METEOROLOGY GROUP / WS8
LYNDON B. JOHNSON SPACE CENTER
HOUSTON TX 77058
600 AM CDT SUNDAY OCTOBER 21 2007

LANDING FORECAST FOR STS-120

EXPECTED LAUNCH TIME: 1538Z
DATE: 10/23/07

RETURN TO LAUNCH SITE (RTLS) - VALID LAUNCH TIME + 25 MINUTES
SHUTTLE LANDING FACILITY... KENNEDY SPACE CENTER FL
KSC SCT030 SCT250 7 15010P15
CHC SHRA WI 20 NM CHC BKN030

TRANS-OCEANIC ABORT LANDING SITES (TAL) - VALID LAUNCH TIME + 35 MINUTES

ZARAGOZA...SPAIN
ZZA SCT090 BKN180 7 32018P28

MORON...SPAIN
MRN SCT200 7 26008P13

ISTRES...FRANCE
FMI SCT090 BKN200 7 34018P28

ABORT-ONCE-AROUND SITE (AOA) - VALID LAUNCH TIME + 90 MINUTES
NOR SKC 7 36012P20

PRIMARY LANDING SITE (PLS) - VALID 10/23/07 20Z TO 10/23/07 21Z
EDW SKC 7 05014P24

FLIGHT RULE VIOLATIONS:
KSC ... CIG/PRECIP
EDW ... NONE
NOR ... NONE
ZZA ... HWIND
MRN ... NONE
FMI ... HWIND

THE NEXT SCHEDULED FORECAST WILL BE ISSUED 22/1000

KSC ...KENNEDY SPACE CENTER...FL
ICAO ID IS KTTS
EDW ...EDWARDS AIR FORCE BASE...CA
ICAO ID IS KEDW
NOR ...NORTHRUP STRIP WHITE SANDS SPACE HARBOR...NM
ICAO ID IS KE28 (KHMN IS NEARBY)
ZZA...ZARAGOZA SPAIN
ICAO ID IS LEZG
MRN...MORON SPAIN
ICAO ID IS LEMO
FMI...ISTRES FRANCE
ICAO ID IS LFMI

LAFOSSE, ORAM, VAN SPEYBROECK

rdale · « **Reply #2 on:** 10/21/2007 01:22 pm »

I'm coming back online finally as our tornado recovery slows down...

And count me less pessimistic for now, the computers are ALL over the place with the big picture pattern but the general trend is for less activity over Florida the next few days. So right now I go 60% acceptable weather for a Tuesday launch, 50% Wed, 80+% Thursday on our...

rdale · « **Reply #3 on:** 10/21/2007 05:02 pm »

Wow - new data helps absolutely NOTHING! One computer now brings the front in Wednesday, then turns it around and moves the low pressure backwards. Not quite sure what that thing is smoking but I want some :>

The other brings the front through and stalls it, giving fairly quiet weather Tue/Wed then nothing but rain Thursday - Sunday! (This morning it had 10% chance of rain through that timeframe.) As Kathy explained in the second presser today, upper-level systems are MUCH more difficult to form if simply because we don't have nearly the amount of measurements. At the surface we get reports on averege every 20-30 miles at least hourly. Upper levels we get every 300 miles twice a day!

TrueBlueWitt · « **Reply #4 on:** 10/21/2007 05:03 pm »

Quote

rdale - 21/10/2007 9:22 AM

I'm coming back online finally as our tornado recovery slows down...

Glad to have you back!

BTW.. Great coverage during the storms the other night. I was watching and listening to you all evening.

Hope you don't mind I outed your TV personality status(and why you were tied up) in the other thread when they were talking about weather probabilities and waiting for you to updated.

rdale · « **Reply #5 on:** 10/22/2007 04:03 am »

Thanks for the words...

Quick look before heading to bed - newest data from ALL computers has only a small chance of a shower on Tuesday (20%) with just clouds being the issue.

dsmillman · « **Reply #6 on:** 10/22/2007 12:02 pm »

The weather channel is predicting good weather for Cape Canaveral until 1 PM Tuesday.

Rocket Guy · « **Reply #7 on:** 10/22/2007 12:05 pm »

They upped it to 60% chance of violation this morning.

psloss · « **Reply #8 on:** 10/22/2007 12:33 pm »

Yeah, the forecast has changed with respect to the second front, too...now predicting that will come NET the end of the week. I'm sure there will be more elaboration at the count status briefing this morning.

SimonShuttle · « **Reply #9 on:** 10/22/2007 12:41 pm »

Have they ever got a shuttle off at 60 percent before? Just trying to work out the percentage borderline for weather....and if 60 percent is pretty much "hardly a chance"?

psloss · « **Reply #10 on:** 10/22/2007 01:12 pm »

Quote

SimonShuttle - 22/10/2007 8:41 AM

Have they ever got a shuttle off at 60 percent before? Just trying to work out the percentage borderline for weather....and if 60 percent is pretty much "hardly a chance"?

Sure. It happens -- I think if you go look at the forecast for the second STS-116 launch attempt, it was 70% chance of weather violation at tanking and they launched.

Another example that I've cited here more than once was for the last launch I saw in person, STS-105. The first attempt forecast was 40% chance of weather violation going into tanking and they scrubbed for 24 hours at either T-9 or T-5. The forecast for the next day was 70% chance of weather violation and they launched.

I always keep an eye on the weather forecasts and Rob's posts, but the first big decision point is at the tanking meeting. If they tank, I'll be here regardless of the forecast.

Acceptable weather is also required for at least one TAL site, and they've scrubbed for that when the KSC weather was go.

rdale · « **Reply #11 on:** 10/22/2007 01:54 pm »

I'm still doing okay with Tuesday's weather, but as per my post yesterday morning it seems like the system will hang up over the southeast instead of sweeping out to sea. The NAM computer (short-term) still has something that I don't think is physically possible so that's useless.

So odds are still better than even that we can launch tomorrow, but if not - odds are not good for the rest of the week.

CTdave · « **Reply #12 on:** 10/22/2007 02:13 pm »

Well...........
I think we are getting on the plane. I appreciate all of your imput & will check it up to the last minute (leave home at 3:45p.m.).
I'd look like a fool for sure with my kids if we didn't go & Discovery went up tomorrow.

ChrisC · « **Reply #13 on:** 10/22/2007 04:39 pm »

Wasn't there a recent attempt where they had 90% violation odds and they actually launched? Might have been an ELV launch ...

rdale · « **Reply #14 on:** 10/22/2007 05:25 pm »

Remember what percentages mean - 90% means 1 time out of every 10 they will launch given those forecast conditions...

Thorny · « **Reply #15 on:** 10/22/2007 05:45 pm »

Quote

ChrisC - 22/10/2007 11:39 AM

Wasn't there a recent attempt where they had 90% violation odds and they actually launched? Might have been an ELV launch ...

STS-93 had a weather forecast of '100% Go' for its first launch attempt. Yet, there were thunderstorms offshore at launch time and they had to scrub.

I don't think I've ever seen a "100% favorable" forecast since that embarrassment (Hillary Clinton had been at KSC for that attempt.)

dsmillman · « **Reply #16 on:** 10/22/2007 05:46 pm »

On the weather channel at:

http://www.weather.com/outlook/travel/vacationplanner/hourbyhour/USFL0066?begHour=1&begDay=296

They show for Cape Canaveral:

at 11AM - 0% of rain, at 12 Noon - 10% chance of rain, and 1PM - 30% chance of rain.

Either the weather channel is wrong or the Cape meteorologists are wrong.

rdale · « **Reply #17 on:** 10/22/2007 06:36 pm »

Please no posting of The Weather Channel or any other automated output - that's from a computer only, with no meteorologists looking at the data. It's useless when trying to predict showers with a computer by itself.

psloss · « **Reply #18 on:** 10/22/2007 06:59 pm »

Quote

Thorny - 22/10/2007 1:45 PM

STS-93 had a weather forecast of '100% Go' for its first launch attempt. Yet, there were thunderstorms offshore at launch time and they had to scrub.

I don't think I've ever seen a "100% favorable" forecast since that embarrassment (Hillary Clinton had been at KSC for that attempt.)

You're referring to the second attempt on 22 July 1999. The weather was fine for the first STS-93 attempt two days earlier; that one was cutoff at T-7 seconds due to a false sensor indication.

IIRC, Clinton was at both of those attempts and didn't return for the third tanking the next night, which is when they launched.

rdale · « **Reply #19 on:** 10/22/2007 08:28 pm »

Links to the USAF observations and additional forecasts:

http://www.patrick.af.mil/shared/media/document/AFD-070711-083.pdf