Mission Plan:
Primary Mission : Lagranagian Experiment continuation. Alternate Mission: N/A Future Mission(s): Lagrangian Flights continue through 2300 UTC, 24 Nov (1100 LDT, Sat 25 Nov.).Aircraft Operations
Take-off Time: N/A Flight #14:01:45 LDT(Fri, 24 Nov); 1445 UTC (Thu, 23 Nov) Flight #15:13:45 LDT(Fri, 24 Nov); 0245 UTC (Fri, 24 Nov) Flight #16:01:45 LDT(Sat, 25 Nov); 1445 UTC (Fri, 24 Nov) Pre-flight Weather Briefing Time: Flight #14: 23:45 LDT (Thurs. 23 Nov); 1245 UTC (23 Nov) Flight #15: 11:45 LDT (Fri. 24 Nov; 0045 UTC (24 Nov) Updates: none Airborne Mission Scientist: Flight #14: Lenschow Flight #15: Huebert Flight #16: Lenschow Mission Scientist: Flight #14: Huebert Flight #15: Lenschow Flight #16: HuebertShip Operations
Discoverer: Discoverer is on station for Lagrangian at 50S 138E as of Weds. evening. The ship was moved to 50S 138E early Thursday to better position itself for tracking balloon launches at the start of the Lagrangian mission. Four balloons were launched at 2340, 0200, 0300 and 0400 UTC. All were tracked by the ship until out of range. Ship was underway moving east from 50S, 138E by approx. o430UTC 23/11. Detailed measurement values available on status page accessed below on catalog. Soundings are taken every three hours form 1200 22/11 through 1200 23/11. Discoverer Lead Scientist: Tim Bates Southern Surveyor: Southern Surveyor is on station at Trans-P2 (45S 142.5E). They will remain there for 30 hours. Soundings being taken every 12 hours. Thereafter, they will proceed to 46S, 148E to begin measuremtns in support of the continuing Lagrangian mission. See catalog reference below for detailed instrument status. Southern Surveyor Lead Scientist: Bronte Tilbrook
48 hour MSL P Prognosis is here
72 hour MSL P Prognosis is here
Latest Visible Sat Picture is here
Surface Wind 24-h forecast is here
BMRC Hysplit trajectories are here
GASP trajectory analysis is here
Synoptic Situaton at 00Z Thursday 23/11/95: Low 999 hPa near 47S 150E moving SE at 20 knots forecast to be near 50S 152 E at 12z tonight then weakening as it passes to the north of Macquarie Island tomorrow.
Cold front near 55S 142E/50S 141E/45S 134E/40S 134E moving E at 10/15 knots and slowing. Front forecast to be near 55S 158E/50S 155E/43S 150E. A weak low 1005 hPa has formed on the front near 43S 132E but most progs seem to dissipate this during the next 12 hours.
High west of Western Australia is ridging in behind the front and is forecast to be near 40S 132E at 00Z tomorrow and near 40S 137E at 12Z.
Deep low below 965 hPa forecast to develop near 52S 120E by 12Z Sunday night.
Prognoses: 0-24 hours: The cold front should continue to move eastwards through the ACE area and cross Macquarie tomorrow afternoon. As mentioned above, the low on the front near 43S 132E is quite weak and the EC prog does maintain it as a surface feature for the period. The balance of opinion of the other models however, is that the low will not survive and the front will reform and continue to move eastwards through Tasmania
24-72 hours: Apart from the low near Tasmania, the progs are in good agreement for the period, bringing the next ridge into the ACE area, ahead of the next front which is likely to move into western parts 12Z Saturday night. Southwesterlies should persist over the Macquarie area following tomorrow's front and ahead of the next ridge, ensuring a continuation of chilly (!!) Spring conditions.
FORECASTS:
Cape Grim: Weather: Showers developing this evening and increasing tomorrow morning with the front. Further showers tomorrow and becoming colder following the change. Winds: West to southwest winds 10/15 knots tending northwesterly this evening and increasing to 20 knots ahead of a 25/30 knot southwest change tomorow morning. Southwesterlies possibly reaching 25/35 knots tomorrow afternoon then moderating late tomorrow evening.
Macquarie Island: Weather: A little drizzle, low cloud and/or fog increasing to rain overnight then easing to showers following the front. The chance of a lirttle hail following the change. Winds: NE/NW winds 15/25 knots increasing to 25/35 knots early tomorrow ahead of a 25/30 knot NW/SW change around the middle of the day.
R/V Discoverer Weather: A few light showers or drizzle patches but mostly fine while you continue to track eastwards following the front. Winds: Chiefly southwest winds 10/20 knots gradually increasing to 15/25 knots tomorrow afternoon. Seas rsing 2 to 3 metres tomorrow afternoon. Westerly swell 2 to 3 metres.
R/V Southern Surveyor Weather: Rain or showers increasing ahead of the front tonight then easing to a few showers following the front overnight/early tomorrow. Winds: Northwest winds 15/25knots easing to 10/20 knots and turning southwesterly with the front. Southwesterlies slowly increasing to 15/25 knots tomorrow. 2 to 3 metres seas decreasing for a period overnight then increasing to 2 to 3 metres again tomorrow. West to northwest swell to 2 metres tending west to southwesterly and increasing to 2 to 3 metres tomorrow morning.
REVIEW OF PREVIOUS DAY: The front has moved into the ACE area much as was forecast, but the development near 43S 134E has generated more high cloud (mostly cirrus) than was expected, shrouding the lagrangian target area. However, from satpics, not much low cloud is evident. On the Discoverer, winds have been lighter than forecast and showers have not yet redeveloped in the cold air. However, the front and low complex have slowed, so the ship is now able to maintain pace with the clearer and therefore weather free area following the front. Showers cleared at Cape Grim as was forecast and winds have followed their expected variations. The ridge over the Macquarie area has resulted in quite moist conditions at the station, however lack of obs at the ACE Ops Centre prevent me from giving a more complete picture. The last obs received from the Southern Surveyor was 21z this morning when things were behaving themselves both win and weather wise. Weather at the other platforms
