.. _TitCase20181219:

Case Description: 19 December 2018
==================================

Summary
-------

Convective initiation and growth over site within a complicated background field

Description
-----------

Convection early during the day persists around the region, potentially complicating model initialization, before the convective initiation over the site at 15 UTC. The system develops until 17:30 UTC after which it decays. CAPE values are in the lower third of their ranges (at 16 UTC MUCAPE=1096; MLCAPE=532 J kg\ :sup:`-1`\ ).

Available assets
----------------

CSAPR2, CSU C-Band data

Unavailable: GOES rapid scan, G1, RELAMPAGO data (RELAMPAGO’s last mission was on 16-Dec)

Critical period: 15:00–19:30
----------------------------
| 15:00 System initiates over AMF and grows
| 15:30 Another initiates to the north
| 16:15 Systems have merged
| 17:30 Largest size has been attained and dissipation begins
| 19:30 System has dissipated while advecting out of domain


.. figure:: images/SatIR-20181219_1730.png
    :name: FigCase20181219
    :align: center
    :alt: Brightness temperature, 2018-12-19 17:30 UTC
    :figclass: align-center

    GOES16 band 13 brightness temperature at 2018-12-19 at 17:30 UTC. System of interest near its peak development.


Available LES ensemble members
------------------------------

.. list-table:: Summary of LES cloud behavior for 2018-12-19
    :name: TableLES20181219
    :header-rows: 1
    :class: tight-table
    :widths: 15 15 70

    * - Impression
      - Ensemble Member
      - Cloud Behavior
    * - Poor
      - EDA09
      - Severe underprediction of convective area. CSK Skill only a fraction of that for the respective meso run.
    * - Poor
      - EDA09-Morr
      - CSK Skill double that of respective meso run but with convective area that is much broader than observed, over extending to the west and far east of observed area.
    * - Eh
      - GEFS10-Morr
      - Initiates northwest behind the ridge and moves in to initiate cell over the AMF while the transition in the observations is from the southwest. About 16:15, a northern cell has developed in the observations to match that in the simulation that had propagated in.


.. raw:: latex

    \clearpage