Over Northeast China, the area surrounding the Horqin sandy land (HSL) is an important plantation domain within the "Three north" Area of China. Compound heat waves and droughts can exert exceptionally negative impacts on ecosystems. However, less attention has been paid to the physical causes of the variability of the frequency compound droughts and heatwaves in this peculiar sandy region. In this study, salient climatic factors tied to the variability of the number of compound drought and heatwave day (CDHD) around HSL in late summer (July-August) are identified. Results show that the preceding wintertime El Ni & ntilde;o-Southern Oscillation (ENSO)-associated SST mode can exert significant delayed impacts on the interannual CDHD fluctuations around HSL in the following late summer, serving as a precursory oceanic factor. Dynamical and thermodynamical diagnoses associated with the observational evidences and the Community Earth System Model version 2 (CESM2) tropical Pacific pacemaker experiment outputs reveal and confirm that the negative phase of ENSO (i.e. La Ni & ntilde;a-associated sea surface temperature mode) in the prior winter can exert cross-season impacts on the enhanced CDHDs around HSL in the subsequent late summer through a critical synchronous atmospheric bridge of the western North Pacific cyclonic anomaly. This system may connect an anticyclonic anomaly prevailing over Northeast Asia via an anomalous meridional overturning circulation, which could act as a salient synchronous atmospheric factor. In this circumstance, favorable in situ meteorological and land surface conditions (e.g., increased 2-m maximum air temperature and suppressed rainfall/soil moisture deficiency) can be established, eventually sparking abnormal heat and drought conditions surrounding HSL and thus producing more late-summer CDHDs around HSL.