WRF-ARW Variational Storm-Scale Data Assimilation: Current Capabilities and Future Developments

<table>Length scales of forecast errors of the WRFVAR control variables of stream function (<svg height="13.225" id="M75" style="vertical-align:-3.56265pt" version="1.1" viewbox="0 0 11.2375 13.225" width="11.2375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,8.737)"><path d="M642 419q-50 -36 -71 -94q-28 -78 -68 -170q-39 -89 -114 -135q-34 -21 -83 -31l-45 -219l-31 -31q-8 7 -15 29.5t-2 45.5l35 172q-153 10 -153 169q0 28 6 84q7 68 7 88q0 48 -27 48q-18 0 -51 -28l-7 26q62 75 118 75q49 0 49 -90q0 -47 -5 -81q-10 -72 -10 -108
q0 -117 82 -133l87 455l62 19l7 -2l-99 -478q91 12 131 120q34 93 51 154q20 73 36 88q42 40 103 56z" id="x1D713"></path></g>
</svg>), unbalanced velocity potential <svg height="17.6625" id="M76" style="vertical-align:-4.3871pt" version="1.1" viewbox="0 0 28.799999 17.6625" width="28.799999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,12.138)"><path d="M300 -147l-18 -23q-106 71 -159 185.5t-53 254.5v1q0 139 53 252.5t159 186.5l18 -24q-74 -62 -115.5 -173.5t-41.5 -242.5q0 -130 41.5 -242.5t115.5 -174.5z" id="x28"></path></g><g transform="matrix(.017,-0,0,-.017,5.944,12.138)"><path d="M565 434q-29 -30 -107.5 -131t-125.5 -168q22 -126 55 -265q8 -35 12.5 -45.5t11.5 -10.5q26 0 76 59l23 -23q-77 -111 -134 -111q-42 0 -63 96l-43 222q-148 -211 -219 -335h-10q-30 45 9 103l209 291q-27 155 -42 214q-7 27 -11.5 35.5t-12.5 8.5q-19 0 -62 -57l-21 21
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<g transform="matrix(.012,-0,0,-.012,15.838,17.45)"><path d="M515 96q-37 -44 -84.5 -76t-71.5 -32q-12 0 -18 7t-6 34t10 75l19 89h-2q-87 -113 -181 -176q-43 -29 -83 -29q-46 0 -46 63q0 31 9 67l52 222q7 36 -1 36q-10 0 -76 -50l-13 24q47 45 92 71.5t67 26.5q18 0 21 -16.5t-8 -65.5l-56 -242q-16 -67 13 -67q41 0 114 74
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<g transform="matrix(.017,-0,0,-.017,22.862,12.138)"><path d="M275 270q0 -296 -211 -440l-19 23q75 62 116.5 174t41.5 243t-42 243t-116 173l19 24q211 -144 211 -440z" id="x29"></path></g>
</svg>, unblanced temperature (<svg height="15.8375" id="M77" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 18.475 15.8375" width="18.475" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.55)"><path d="M649 676l-22 -187l-33 -2q3 56 -12 94q-8 20 -31.5 26.5t-86.5 6.5h-74l-90 -491q-4 -23 -6 -36.5t1 -25t7 -16.5t18 -9t27 -5t41 -3l-6 -28h-286l4 28q68 5 84 18.5t28 76.5l94 491h-55q-74 0 -100.5 -6t-41.5 -23q-24 -29 -54 -98l-32 1q32 98 53 188h22q7 -18 15 -22
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<g transform="matrix(.012,-0,0,-.012,11.388,15.637)"><path d="M515 96q-37 -44 -84.5 -76t-71.5 -32q-12 0 -18 7t-6 34t10 75l19 89h-2q-87 -113 -181 -176q-43 -29 -83 -29q-46 0 -46 63q0 31 9 67l52 222q7 36 -1 36q-10 0 -76 -50l-13 24q47 45 92 71.5t67 26.5q18 0 21 -16.5t-8 -65.5l-56 -242q-16 -67 13 -67q41 0 114 74
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</svg>), and relative humidity (rh), with respect to the vertical EOF mode, computed using 3 km WRF forecasts over a domain that covers a region of N24°–N49° and W116°–W74° in the USA. Note that the surface pressure has only one mode (indicated by the purple *) because it is a 2D field. </table>

Advances in Meteorology

fig1

Figure 1

Figure 1: WRF-ARW Variational Storm-Scale Data Assimilation: Current Capabilities and Future Developments 