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Solar-induced chlorophyll fluorescence (SIF) has been shown to be a powerful proxy for photosynthesis and a promising indicator of drought monitoring, but the ability of high-resolution satellite-derived <i>SIF</i> for drought monitoring has not been widely investigated due to a lack of data. The lack of high spatiotemporal resolution satellite <i>SIF</i> hinders the resolution enhancement of <i>SIF</i> derived by downscaling or reconstruction algorithms. The TROPOspheric Monitoring Instrument (TROPOMI) <i>SIF</i> provides an alternative with finer spatiotemporal resolution. We present an operational downscaling method to generate 500 m 16-day <i>SIF</i> (TSIF) using Neural Networks over a local spatiotemporal window. The results showed that our method is very robust against overfitting, and TSIF has a strong spatiotemporal consistency with TROPOMI <i>SIF</i> (TROPOSIF) with <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi mathvariant="normal">R</mi><mn>2</mn></msup><mrow><mo>=</mo><mn>0.956</mn></mrow></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>RMSE</mi><mo>=</mo><mn>0.054</mn><msup><mrow><mrow><mtext> </mtext><mi>mWm</mi></mrow></mrow><mrow><mrow><mo>−</mo><mn>2</mn></mrow></mrow></msup><msup><mrow><mi>sr</mi></mrow><mrow><mrow><mo>−</mo><mn>1</mn></mrow></mrow></msup><msup><mrow><mi>nm</mi></mrow><mrow><mrow><mo>−</mo><mn>1</mn></mrow></mrow></msup></mrow></semantics></math></inline-formula>. Comparison with another <i>SIF</i> product (CASIF) showed a spatiotemporal consistency with TSIF. Comparison with tower gross primary productivity (GPP) from AmeriFlux in California showed a strong correlation with <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi mathvariant="normal">R</mi><mn>2</mn></msup></mrow></semantics></math></inline-formula> for multiple ecosystems ranging from 0.58 to 0.88. We explored the capacity of TSIF for monitoring a drought event in Henan, China, showing that TSIF is more sensitive to drought and precipitation compared to the Enhanced Vegetation Index. Our TSIF is a very promising indicator for regional drought monitoring.