Why 1-minute data matters: Orphan Anvils

June 4th, 2015 |
GOES-14 Visible (0.6263 µm) Imagery, 11 May 2014.  An orphan anvil is indicated (click to play animation)

GOES-14 Visible (0.6263 µm) Imagery, 11 May 2014. An orphan anvil is indicated (click to play animation)

‘Orphan anvils’ typically will develop before and just as a cap that prevents convective development breaks down. They can therefore be a precursor to strong thunderstorm development. The animation above shows an orphan anvil just before strong convection (Storm Reports) develops over south-central Nebraska. The anvil development is obvious in the 1-minute animation, above. (Click here for an un-annotated, smooth animation). This anvil was mentioned in the SPC Day-1 Convective Outlook updated at 2000 UTC (the 1-minute imagery is called 1km in that outlook).

The animation below compares 1-minute (top), 5-minute (middle) and present 15-minute GOES (bottom) time-steps over northwest Kansas on June 4 2015. It is a straightforward matter to notice the orphan anvils in the 1-minute imagery; it is far more challenging when using the 5-minute time-step and it’s nearly impossible with present-day 15-minute GOES time-steps. In this case, the cap was not broken. (Hat tips to Bill Line, SPC and Chad Gravelle, OPG, for these cases; Click here for additional comments and here for additional information on SRSO-R Operations).

GOES-14 Visible (0.6263 µm) Imagery, 4 June 2015, with 1-minute time-steps (top), 5-minute time-steps (middle) and routine 15-minute GOES time-steps (bottom) (click to play animation)

GOES-14 Visible (0.6263 µm) Imagery, 4 June 2015, with 1-minute time-steps (top), 5-minute time-steps (middle) and routine 15-minute GOES time-steps (bottom) (click to play animation)

Leave a Reply