Will SpaceX Falcon 9 launch?

[Korina]

Update: 28th of May 02:00 p.m. UTC

SpaceX launch of NASA Astronauts is postponed over the weather

Thunderstorms and light rain caused by Tropical Storm Bertha were the reason why mission Commercial Crew Demo-2 was aborted only 17 minutes before liftoff.

The Next attempt is scheduled for Saturday, 30 May at 7.22 PM UTC (3.22 PM EDT).

Although chances for success look similar, stormy weather with cloud cover is predicted, upper winds, which can drive thunderstorms to the coast, might be better. On the day of supposed launch, upper winds were moderate (13 kt/24 km/h), on Saturday will be light (4kt, 8 km/h).

In case the launch will be postponed again, the backup launch window for Falcon 9 is available 31 May at 7 PM UTC (3 PM EDT), with the same probability for success.

Update: 27th of May 01:00 p.m. UTC

The SpaceX first-ever crewed spaceflight is scheduled to take off from Cape Canaveral in Florida later today as a mission Commercial Crew Demo-2.

The launch is currently set to 08:30 p.m. (4:33 PM EDT) from Kennedy Space Center, however the weather conditions are not looking very favorable. There is currently a 50% chance that clouds and stormy weather will delay the proceedings due to violating the safety guidelines.

The Crew Dragon capsule will initially spend 19 hours orbiting the Earth till reaching the International Space Station on Thursday.

If the launch ends up to be postponed, another opportunity to send the capsule into the orbit will be on Saturday 30th May.

https://www.windy.com/upload/5ece9129f8e856001d015140?radar,28.229,-81.088,9,internal

[100ideas]

Some more useful links:

SpaceX/NASA livestream (live now as of 1pm EDT 27 May 2020)

2D telemetry simulation & 3D trajectory visualization
https://flightclub.io/live

reddit knows all https://www.reddit.com/r/spacex/comments/glwz6n/rspacex_cctcap_demonstration_mission_2_general/

SpaceX offical overview page http://spacex.com/launches

my curated twitter list of peeps who know whats up w/ the launch https://twitter.com/i/lists/1265607251542315013

[100ideas]

What windy chart modes in particular do the mods / experts think might be most useful for assessing scrub likelyhood at canaveral this afternoon?

Here's a windy-embed src link showing projected lightning strike density at 4PM EDT (0.14l/km^2)

https://embed.windy.com/embed2.html?lat=28.610&lon=-80.606&zoom=8&level=surface&overlay=thunder&menu=&message=&marker=true&calendar&pressure=true&type=map&location=coordinates&detail=&detailLat=28.249&detailLon=-79.934&metricWind=default&metricTemp=default&radarRange=-1

according to ECMWF, the lightning strike data are represented in derived units of, l/km^2 or "average strikes per square kilometer per hour", interpolated/rescaled from a more course-grained primary prediction output with units of strikes/km2/day on a spatial and temporal scale of tens of kilometers & 6-hour block respectively.

Lightning confluence.ecmwf.int/display/FUG/Lightning
A new "lightning flash density" forecast product was introduced in Cycle 45r1, released in June 2018. This can be viewed within ecCharts. The units of lightning flash density as archived are "strikes/km2/day", but these are rescaled for ecCharts usage to "average strikes/km2/h". The product is derived from HRES and ENS, with ecCharts ENS representation being probabilistic (to exceed a certain density threshold). The threshold and period duration for the probabilities are under user control.
The diagnostics aim to represent cloud-to-ground plus intra-cloud lightning strikes. Note that many ground-based lightning sensing systems are much more adept at identifying cloud-to-ground strikes.

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[Gkikas LGPZ]

With all those isolated tstms passing through
the Go / No-Go is a tough decision.
This decision must be taken 45 min. before lift off.

[Gkikas LGPZ]

SpaceX's Demo-2 mission has been delayed by bad weather
and will now launch on Saturday, May 30, at 3:22 p.m. EDT (1922 GMT).

[Gkikas LGPZ]

The latest ECMWF run
shows stormy weather for Sat, 30 May, 19Z.

[Gkikas LGPZ]

.... the good news are that for Sat, 30 May afternoon
the upper winds
(which drive the thunderstorms from mainland Florida to the coast)
will be very light (3 kts) from south direction
and are not expected to push tstms towards Cape Canaveral.
I remind you that yesterday's upper winds were moderate (13 kt) from SW.

Although the go/no go seems a difficult decision,
we must remember that a decision is difficult when there is no best option.

[Gkikas LGPZ]

The following weather criteria must be satisfied for Crew Dragon to launch:

[Gkikas LGPZ]

Launch Mission Execution Forecast (by 45th Weather Squadron)