Brief, 20140115•Easterly wave passed last night, with followup band of northward propagating convection•Forecast is for substantial drying and weakening of trades through Saturday.•Temperatures over Guam as low as 187K at tropopause, roughly consistent with models. Models predict very slight cooling of Guam temps by landing.•Cruise altitude temperatures within aircraft temperature limits.•Long range forecasts SUGGESTS convection increasing in our part of the Pacific (MJO).•Forecast 100mb temperatures indicate entering a cold phase that is propagating slightly westward (at 10N).•Anticyclone in western Pacific is strong, with low EPV air to between 100 and 70 mb.

Last night’s sounding (left) shows minimum T at 187K (53kft) over Guam. This occurred during rainstorm, had moist sounding to above 600mb. By this morning (right) have significant drying. These disturbances are not deep!

This morning (left). Line of showers following major disturbance last night. Strong anticyclone, leading to strong trades. Showers “bring down” winds from aloft leading to 30 plus gusts this morning.

Landing time (Friday AM -- right). Weaker gradients, note frontal system (called a shear line in the tropics) is moving in at 20N. Trades are much weaker. Expect ENE winds of 10-15 knots at landing

View at 10 kft. Above (about now) shows disturbance just past us to the west, changing to very dry conditions by takeoff time.

At landing, we are in a dry slot. Some moisture, but vertical winds much weaker than yesterday’s disturbance.

Sunday evening a shear line approaches. Longer range models indicate it will not pass, but winds will increase, as will the likelihood of showers. Early next week will not be as benign as landing time Friday, but still flyable.

Current situation (approximate min temp). Guam shows about 188K, radiosonde says 187K. Coldest temps to the east of Guam. Minimum temps at 55kft or lower (below cruise).

Conditions at landing (minimum temperature). Temps just slightly colder over Guam than today. Forecast tropopause is 53-55 kft. These temps are roughly consistent with the radiosonde.

Hard copies of en route temperature curtains and winds.

Temperature curtain along the flight path (from Leslie).

MJO Evolution – MJO projected to amplify “in place” with stronger west pac convection.

Brief, 20140115•Easterly wave passed last night, with followup band of northward propagating convection•Forecast is for substantial drying and weakening of trades through Saturday.•Temperatures over Guam as low as 187K at tropopause, roughly consistent with models. Models predict very slight cooling of Guam temps by landing.•Cruise altitude temperatures within aircraft temperature limits.•Long range forecasts SUGGESTS convection increasing in our part of the Pacific (MJO).•Forecast 100mb temperatures indicate entering a cold phase that is propagating slightly westward (at 10N).•Anticyclone in western Pacific is strong, with low EPV air to between 100 and 70 mb.