MSEAS EM-APEX Float Reachability Forecast for 04 Sep 0000Z to 12 Sep 0000Z 2025, Issued 04 Sep 2025

This is a float reachability forecast, using the anticipated starting locations of 3 EM-APEX floats on 04 Sep 0000Z, starting from a 7-day PE forecast (which covers the period Aug 28 - Sep 12).

Starting points are located where the floats are anticipated to be at 0Z on 04 Sep 0000Z. All runs assume 3 cm/s velocity unc., and run for 8 days.

In the plots below, the overlaid velocity vectors are those that the float "sees". This is a single velocity field constructed assuming that the float does either one or two up/down profiles a day (0 to 1500m), taking 8.5 hours per profile and spends the rest of the day "parked" at 1500m.

The resultant velocity fields consists of:

• For 1 profile/day: 8.5/24*(0-1500m vertically averaged velocity) + 15.5/24*(1500m velocity) field
• For 2 profiles/day: 17.0/24*(0-1500m vertically averaged velocity) + 7.0/24*(1500m velocity) field

Reachability Summary

Profs/day	Starting Point 1	Starting Point 2	Starting Point 3
2
1

Details of Reachability Front and Velocity Field Evolution

Profs/day	Start point	20250904	20250905	20250906	20250907	20250908	20250909	20250910	20250911	20250912
2	1
	2
	3
1	1
	2
	3