the misadventures of weather boy

Saturday, December 09, 2006

Second attempt works

The second launch attempt for STS-116 worked as Discovery lifted off at 10/0147Z this evening. Landing is scheduled for 21/2117Z in Florida.

Takeoff image just as Discovery clears the tower. AP image by Chris O'Meara.

METAR KRDU 100251Z 23504KT 10SM CLR 00/M08 A3051 RMK SLP335

Labels: space

Thursday, December 07, 2006

STS-116 scrubbed tonight

Tonight's launch of Discovery was scrubbed when the launch window ran out of time. Glancing out the following observation:

METAR KTTS 080225Z 31008KT 10SM OVC055 16/06 A3019 RMK SLP223 8SC /8/ N3310/15 C3309/14 S3108/13

Overcast skies at 5,500 feet at the conclusion of the T-9 minute hold was enough to scrub things (they need a ceiling of 8,000 feet to launch). The clock was held at T-5 minutes to hope that things might clear up, but by 9:35 ET, time had run out (the launch window went until 9:40, and so T-5 minutes at 9:35 ET means that that is the latest time to resume the countdown).

Tomorrow may not be any better; surface winds are forecasted near 15kt (which implies that they'll be faster higher up). The next SMG landing forecast is at 06Z (1am), so it'll be an interesting outlook.

METAR KRDU 080151Z 31510G18KT 10SM BKN090 02/M08 A3023 RMK SLP240

UPDATE: They'll try again Saturday at 8:47pm ET (10/0147Z).

Labels: space

Saturday, July 15, 2006

Shuttle landing forecasts

As I noted earlier, I would lend some interpretation to landing forecast when the SMG included Monday in its landing forecast. This morning, we get the first look at the landing forecast for Monday and Tuesday. NASA has budged its projected landing time in Florida slightly to 9:14am EDT (1314Z). Based on the inclinations of the earlier local forecasts, it is unlikely that the shuttle is touching down in Florida this mission either.

Among other concerns, the shuttle cannot land in a ceiling under 8000 feet, in precipitation, or windy conditions.

"Perma"link to this forecast. Use this link for the latest forecast.
First try:

SHUTTLE LANDING FACILITY...KENNEDY SPACE CENTER FL
 FIRST OPPORTUNITY
 KSC  FEW020 BKN100 BKN250           7              26003P05
      CHC SHRA WI 30

Meaning: < 25% coverage at 2000 feet, 75% coverage at 10000 and 25000 feet (ceiling=10000 feet, okay). Visibility 7 statute miles (good). Winds out of 260 degrees (from the west) at 3 knots (about 4MPH), peaking to 5 knots. The big issue is the last line–chance of showers within 30 nautical miles. The NWS forecast currently lists "scattered afternoon showers", and the chance part seems to indicate a POP of ≤ 20%.

 SECOND OPPORTUNITY
 KSC  SCT025 BKN100 BKN250           7              22005P07
      SHRA WI 30

Meaning: 3/8-4/8 coverage at 2500 feet; ceiling at 10000 feet (good). Visibility 7 miles; winds from southwest at 5-7 knots. Rain showers within 30 nautical miles.

 EDWARDS AIR FORCE BASE CA
 EDW  FEW150 SCT250                  7              20005P08
      WND 20010P15 AFT 17Z

Meaning: <25% coverage at 15000 feet; <50% coverage at 25000 feet (no ceiling). Visibility 7 miles; winds south-southwest at 5-8 knots; winds change to 10-15 knots after 17Z (1pm EDT, 10am PDT).

 NORTHRUP STRIP...WHITE SANDS SPACE HARBOR NM
 NOR  FEW060 SCT120 BKN250           7              16004P07

Meaning: <25% coverage at 6000 feet, <50% coverage 12000 feet, ceiling at 25000 feet. Visibility 7 miles; winds from south-southeast at 4-7 knots.
Edwards should be okay to land at Monday, but Florida is out of the question.

Tuesday: Florida: Ceiling 1000 feet, visibility good, winds from south at 3-5 knots. Change of rain showers within 30 nautical miles.
California: Ceiling 12000 feet, visibility good, winds from south at 5-8 knots.
New Mexico: Ceiling 25000 feet, visibility good, winds from southeast at 5-8 knots.
Looking further forward on the SMG Weather Forecast Sheet, on page 2 there is still a chance of showers within 30 nautical miles on Wednesday.

Given the nature of forecasts, I suspect that NASA will try for Florida on Monday, and should Florida not work out on Monday, it will probably be an Edwards Air Force Base landing on Tuesday.

The next forecast is issued later this evening around 23Z-00Z.

METAR KRDU 151751Z 31505KT 10SM FEW045 SCT090 BKN150 BKN250 32/22 A3001 RMK SLP157 1033 2025

Labels: meteorology, space

Monday, July 10, 2006

Space Shuttle Discovery Landing Forecast

For those of you who care, here is a link to the Spaceflight Meteorology Group's forecast.

Since this is loaded with all of the standard NWS product jargon (some of the SPC products raise abbreviation writing to an art form), I will make a translation when it gets closer to landing (landing forecasts are only two days in advance. In the meantime, you can enjoy the more digestable NWS point forecasts for each site: Kennedy Space Center (Cape Canaveral, Florida), Edwards Air Force Base (California), and White Sands (New Mexico).

Changes to original post in RED.
METAR KRDU 100351Z 18002KT 10SM SCT200 22/17 A3011 RMK SLP192

Labels: meteorology, space